800x480 vs 480x272
But PSP battery life might be better, and it's definitely better for games. Nokia has WiFi. There are other pluses and minuses.
You could probably also use Nintendo GBA Advance, SP, or DS, but the screen is even smaller.
Of course, the real reason to choose the Nokia is that [link|http://pymaemo.sourceforge.net/cgi-bin/moin.cgi/"|it runs Python]