This is just a quick opinion dump that quickly covers the games that I either watched demos for or actively played at E3 2006. Not hard and fast reviews, just off-the-cuff reactions.
Type: combo-based beat-em-up
Experience: Played Live Demo
Thoughts: Beating the crap out of a guy with a lawn chair is one of those things that just never quite gets old, but that may not save this game. The graphics aren't impressive, the game is still very glitchy, and the direction controls are highly finicky as demoed on the show floor. In addition, the combos themselves are just not well designed: triangle-triangle executes a certain attack, triple-triangle another, and triangle-triangle-square a third, for example. In 25 minutes of playing, I never did figure out how to control which of the three combos got triggered. The controls and gameplay generally just leave a lot to be desired. If the game is improved and polished heavily before release, I might pick it up in the bargain bin. Except not, because I don't have a PS2.
Soul of the Ultimate Nation
Type: MMORPG, classic fantasy
Experience: Played Live Demo, PvP Skirmish
Thoughts: This is a gorgeous game. The effects are great, the animations are very nicely done, and the environments are rich. It looks amazing. Unfortunately, it's yet another generic RPG. Thankfully they seem to have avoided the cliche Elves and Hobbits fare, but I'm not sure how many more Fighter-Mage-Rogue parties I want to juggle. MMORPGs just aren't my thing, really, unless they can deliver something really new and interesting. SUN has some creative character designs and abilities, but it's really just the same stuff we've been recycling since D&D.
Type: MMORPG, futuristic/scifi
Experience: Played Guided Demo
Thoughts: I like the innovation in attack style: you have to point roughly at the thing you want to shoot to hell, and then click it to begin automatically shooting. It's a nice medium between highly manual click-once-per-attack games, and virtually self-playing macrofests. The camera needs a lot of work, though, as things tend to get royally confusing when the action gets thick. Being a relatively experienced FPS player, I find it very annoying for MMOs to "pretend" to be FPS/TPS and yet still feel like very clunky tile-based games. This game has also been "ready to come out and change the world" for years, and yet here it is, stuck as usual at 80% or whatever. As I heard someone comment, "E3 just won't be E3 when Tabula Rasa finally gets released."
Lego Star Wars: Classic Trilogy
Type: Action, I guess
Experience: Played Live Demo
Thoughts: This looks like it could be a heck of a lot of fun. I've heard very, very good things about the original Lego Star Wars. Sadly, the demo unit I had was stuck in some dead-zone where it was impossible to progress in the game, and the unit then crashed on me shortly thereafter. So overall a disappointment, but there may be hope; the people around me with functioning units seemed to enjoy it a lot.
Type: Action MMO
Experience: PvP Skirmish
Thoughts: This looks like it could be very, very good. The game we played was a sort of CTF variant where you have energy crystals that you have to stash in your "base." The catch is that the other team can also steal your crystals. This game moves incredibly fast - at about 45 seconds on the clock, our team was winning handily 3-1. By the time the game ended, we had lost 0-4. Gameplay is intense, graphics are good enough to be immersive and give a good experience, and the controls are fairly unobtrusive. My main complaint was that, for such a fast-paced game, the abilities had painfully long casting times, and a couple of the abilities were very hard to figure out how to use correctly with no tutorial. A little fine-tuning on some of the timings and a gentler player introduction, and this could be a very impressive game.
Time Crisis 4
Type: Arcade Shooter
Platform: Custom (lightguns and arcade cabinet)
Experience: Played Live Demo
Thoughts: As a fan of the Time Crisis series, I was very excited to see this game. There's the usual token storyline going on, with some interesting new twists. I won't spoil them. The graphics are absolutely awesome, and deliver a very noticeable advancement to TC3. The guns have been tweaked a bit and feel a lot more deadly now. Despite the updates, though, it still feels very much at home for a TC fan. My only complaint is that the little "incoming damage" warning flashes are very badly timed; whereas in TC2 I can virtually always dodge, TC3 was almost too fast for my tastes - I can't lift my foot off the pedal quickly enough to get out of danger much of the time. TC4 is even harder. Hopefully that'll get tweaked a bit; or maybe I just need to put a couple more points in DEX. I'll definitely shed quite a few quarters on this beauty when I see it in real life.
Platform: Xbox360, maybe others
Experience: Watched theatrical demo
Thoughts: Kind of a yawner; yet another FPS with yet another somewhat cheezy story about the Evil Megacorporation that takes over the world and is secretly killing its army of mercenary soldiers with artificial stimulants. The gameplay video didn't show anything that I haven't seen a dozen times since Doom, and since I don't own a 360, I won't be running out to get one just to play Haze. The backstory is kind of funny though, as it makes several very tongue-in-cheek jabs at the Bush campaign to "freedomize the world with democracy" and such rubbish.
Experience: Watched theatrical demo, watched presentation from Chris Taylor
Thoughts: Yep, Chris Taylor is back in the RTS scene, and it's about bloody time. SC sports a new take on tactical control: you don't have a "scenario-level" map vs. a "detail map" anymore; you can actually smoothly zoom the same map display between the two levels. They're doing full widescreen support and full dual-monitor support. The interface is very elegant and has some cool features like synchronized attacks. Overall this game looks absolutely amazing. There were some guys in line with me for the theatre presentation that had been through the show 7 times; I can't blame them. This is a must-buy for any RTS fan.
Joint Task Force
Experience: Watched presentation
Thoughts: Could be good; looks fairly fun. You can do stuff like have your infantry units hide in the brush and ambush people. Graphics are superb. The gameplay also gets away from the traditional "magically spawn units from factory buildings" paradigm, and actually paradrops in reinforcements, real-life style. It's pretty cool to watch a bunch of guys rope in from a Blackhawk and then be there for you to command. They also have a nifty feature where the map of the battlefield expands dynamically depending on the events of the mission you're on, so you can't just glance at the terrain and predict what you have to do to beat the mission. Overall this game shows a lot of promise, and as an RTS geek, I'll probably buy it eventually (assuming it turns out as well as it looks like it can).
Type: Sandbox, GTA-style
Platform: Not sure
Experience: Watched theatrical presentation
Thoughts: This game is bloody hilarious. It's chock full of crude humour and rough insults, and very much fits the atmosphere of the movie. I'll probably rent it at the very least just to experience all the hilarious stuff. To basically sum up the core of the game, you go around beating up on people and running drug deals to earn "Balls Points." Get enough Balls, and you can take over Miami. Cutting-edge lowbrow entertainment.
Platform: Xbox, and some others I don't care about
Experience: Watched a demo by a Lucasarts marketroid
Thoughts: I'm getting this for sure. Picture Roller Coaster Tycoon, except with the added bonus of being able to talk to all of your customers RPG-style, and with the major bonus of being able to actually ride all of the rides in your park. They even have a set of classic arcade games that you can install as park attractions, and then play yourself as minigames. Basically it's like RCT with a GTA-style mode where you can drop in and just do whatever you want, without worrying about managing the park itself. As a major RCT addict back in the day, I absolutely can't miss this one.
There were a lot of others, but those are the ones I can remember at the moment. I may add more if I recall them later.