Yeah, I have mine pre-ordered through Amazon. I traded in a bunch of games back when Amazon's trade-in program first started and they offered $75 off of the purchase of a console when you traded in $75 worth of games. I ended up trading in about $175, which made the PSP Go essentially free with the promotion.
The promotion made it a pretty reasonable price, so I went for it. The portability was a pretty big contributing factor in going for the Go instead of the 3000. I also like the idea of a completely DD system. My only worry is that the PS Store is really the only place to buy them, which means I won't be able to look for deals like I do for console games. I bet retail will probably end up selling vouchers, so maybe that's a way around that problem.
I'm pretty excited for it. Hopefully, Sony puts a bunch of the past games on the store like they promised. Future releases are looking pretty good, but I want to play the older titles as well.