I dont disagree with that But.
Before multiplayer games going to be a hit on mobile phones
the operators have to lower there prizes on GPRS connections or else this wont be a hit in any near future.
When people been forced to pay 1-2$ for one MB of data (and dont forget you are paying for both send and receiving data).
The next there are to it, is that a game for mobile phones should be a game you can pick up and play for 5-10 minutes or so while you are waiting for a bus (thats my opinion). I dont think that major RPGs or something like that ever going to be a hit on mobile phones because of the small screens and bandwidth prizes even if the prizes is lowered there is the small screen left and lets face it there is other hardware there is better to play that kind of games on.
If you want to make a multiplayer game for mobile phones I think that you should make some casual games where people can connect to a game server and play against each other for 5 or 10 minutes and then log off.
If you think I am missing something or disagree with my thoughts then leave a comment I would like to hear what you are thinking of the subject.
Alternatively there's always bluetooth for local gaming fun and some phones are starting to allow you to connect via wi-fi!
I agree though that 90% of the carriers charge stupid amounts for the data. My carrier is only viable because I'm in London so they have good coverage.