Well, the following night (Wednesday) I managed to rack up 2500 points playing the Flexicon game, so I ordered my prize, a wireless XBox controller (the PC version, which comes with a USB receiver dongle and driver disc). The terms clearly stated that I should wait 6-8 weeks for my prize to arrive.
Surprise of surprises, my controller arrived YESTERDAY MORNING. It works great and is perfect for playing games on the computer hooked up to the downstairs TV.
I've had good luck with Microsoft's shipping in the past. When I order something from 'em with a product rebate, I typically get the rebate in two weeks (compared to the typical 2-3 month cycle).
Note that if you play Flexicon once and it takes you forever and you think there's no way you could beat it enough times to win a prize, note the following:
1. The puzzles get easier as the words repeat. It looks like they have 2-3 clues per word that they cycle through. You'll eventually get the hang of it. I can typically beat a puzzle in 5 minutes.
2. Have a tab opened to http://www.oneacross.com/, which is a crossword helper that lets you enter partial words and get some help.
They've added some new games to the site now, like a couple more word games and a trivia game. Thus-far I haven't found one that can net you points for your time investment as well as Flexicon, but if you find a good one, lemme know.