Okay, this is interesting because they talk a bit about the button placement, and that the things I'll post here:
http://psp.ign.com/articles/991/991051p1.html
"Chris:
The fact that the buttons are a little lower on the system than the current one means that you don't have to form as much of a claw to use the shoulder buttons. There's more distance from the bulk of your hand and your index fingers with the go, which should make it more comfortable in the long run. I hope that the fact that the buttons are flush up against the back of the screen portion doesn't mean that they'll get cramped that way, but so far so good. The shoulder buttons also feel more responsive than the current plasticy-feeling buttons.
The analog stick also felt a little more solid and smooth than the current one, but I'll hold my final judgment on that until I get more time with it.
Scott:
Despite its incredibly compact design, however, the PSP go isn't too small for those same enlarged, semi-adult male hands. My fingers wrapped comfortably around the edges of the device and I didn't have to cramp or arch my fingers to get a good feel on the shoulder buttons. Outside of my concerns about the physical size of the device, another big worry of mine was the positioning of the thumbstick. Again, misled by the in-hand promotional pictures, the thumbstick appeared to be bit of a reach for a player's thumb, but in reality its within a comfortable range.
Greg:
I felt like the nub was in a goofy place, but Roper played it without the holder and said he didn't have the same problem so I think that concern is mainly due to the holder."
----------------------------------------------------------------
This is great, it certainly only strengthens my feeling about getting a PSP Go! 
