I actually had a chance to mess around with one of these at my local used game shop. This machine looks extremely impressive. The unit is the same size as a GBA, but the first thing you'll notice is the screen. It's twice as large as a GBA screen, and three times as clear. It's got a resolution of 480 x 370. Unfortunately I didn't get to play any games, just mess around with the operating system. Unit is skinner than a GBA and has a touch stylus. Machine is supposedly capable of using Palm software as well as running Divx movies, MP3's etc. Comes in 32 and 128 RAM versions. The price difference is like $100, but if you can afford to drop $450 on a new PDA then you might as well get the all the trimmings. Bottom line is if you need a new PDA then you'll drool all over this thing, but at four bills I doubt it'll be a very successful game system.
9/16/2006 - Sure enough, this machine was discontinued less than a year after it's release. Seems like no one even carried it except CompUSA. About 30 or so games got around to being released, nothing much to really talk about though. Stocks of these can still be found in the odd computer store, however even at clearance prices expect to pay at least $80-$100.