Polygons matter little, and I rarely get caught up in spec talks, but I guess I can make an exception.
The PS2 realistically gets between 5 and 10 m polygons/sec, not 10-20 m. The Gamecube normally gets what Nintendo released, and that is 6-12 m polygons, with Rogue Leader getting 15m, the highest of any Game this system. According to Factor 5, it could be up to 20 m with RS3. I don't see the PSP pushing as much poly's as the PS2, so it is probably more like 3-5 m.
I wonder if the PSP will have some PS1 killer apps at launch, plus GTA3. If it does, I can see size, shape, and battery life not factoring in too much. Hardcore Sony fans and people who like GTA and the PS1 games will buy it, tell all their friends about it, and then they will in turn buy it with one game and let it sit on their shelves for years. Thus, the PSP becomes the next big thing, when in reality it is not getting a lot of playtime like the GBA would.
Even though the videogame industry has been rapidly growing over the past years, I don't know if it is necessarily a good thing that it has become mainstream. Some good games and consoles have been overlooked or unheard of by the masses, yet hardcore gamers play them hour after hour, day after day. Yet some rather poor games get hyped and they sell by the truckload, only to sit on people's shelves most of the time. But because those games sell well, the industry is then piled with similar games and more garbage, while developers turn away from creating the really fun and creative games because it is less lucrative. Image, hype, and graphics are driving the industry, not quality and creativity. I've only gone on this little rant because (I'm not bashing Sony) it seems that the mainstream floods to Sony and their Playstation name, and I don't really want the handheld industry becoming mainstream with the coming of the PSP. It seems for the most part handhelds have remained oblivious to the mainstream effects of their console cousins, and IMO it's probably for the better. Competition is fine, but I can only hope that the PSP doesn't bring handhelds mainstream.