For me the best one is the 2000 versions..

They're lighter, slimmer, and overall better than the 1000 versions.. Now, if the 3000 versions are able to hold CFW permanently then i'll switch to the 3000. Until then, it sucks for me.

PSP-Go!.... it looks ugly to me, the overall design sucks ass by having the analog stick right next to the directional buttons.. But it has some good points as well like the 16gb drive and bluetooth. But for me, im undecided if i'd like one or not.

Btw, to be a little off-topic, there's actually a rumor going around about a PSP 4000 version.. It actually came from the words of a sony rep herself.