there's definitely a lot of good RPGs on the PS2, but I can't think of one from Square without Final Fantasy in the title like the PS1 days. On PS2, I'm a huge fan of the Suikoden series, Star Ocean, the original Xenosaga. Square obviously has some talented developers, which is why i think it'd be awesome if they created a new IP.
My Top 5:
Shadow of the Colossus, Metal Gear Solid 3, Shenmue, Skies of Arcadia, Chrono Trigger
My 2 nex-gen systems: PS3 
and Wii 
Prediction Aug '08: We see the PSP2 released fall '09. Graphically, it's basically the same as the current system. UMD drive ditched and replaced by 4-8gb on board flash memory. Other upgrades: 2nd analog nub, touchscreen, blutooth, motion sensor. Design: Flip-style or slider. Size: Think Iphone. Cost: $199. Will be profitable on day 1.
Essay Pro