This device uses the next generation OMAP processor. So yes, it will be a lot more powerful than the N800. The current GP2x F100 is not a very good device in my opinion. The linux software is a lot less finished than Maemo. The original device was useless (the mk-1), the software was buggy and unstable, you couldn't watch a whole movie, the battery life was bad (even if the software didn't crash, two hours was most likely the limit), and the joystick was so bad you couldn't correctly use it for games (not perfectly in one direction).
The MK-II had an improved digital stick, but the bundled mplayer still was unstable.

Only since firmware 3 was the media player somewhat usefull. It didn't crash, but it still had compatibility problems (it can play a lot more files than the N800, but it still isn't fast enough to play all downloaded video files). Also the screen of the F-100 isn't very good. It is low resolution, but that isn't the main problem. The MK-1 had interlace artifacts and the MK-2 had a bad viewing angle. Also the software didn't help: very bad brightness controll and options.

Don't get me wrong it has potential, but my experience with linux devices (GP2x, Nokia IT, Asus WL700 router) has been that the software just isn't finished, and even though the Nokia IT series may not be perfect, the software Nokia has released on these devices is in VERY VERY good "finished" state compared to Gp2x and my asus router.
That is why I'll wait until I see this new product, and am able to test it. (Just like the Asus EEE: I very much doubt Asus has improved quality testing)