There is little to compare the Go too. It isn't really a new model in the traditional sense - rather, it's been designed to support a new retail channel exclusively.
I'm not aware of any other product recently that you could compare it to, other than early adopter 'gadgets' in general and any public comments from Sony
Therefore I don't see it flopping as Sony said it was priced/aimed at early adopters, that initial sales are as expected and it seems to have sold okay for a new gadget with a very small potential install base.
I'm not a fan of Go as such, but going by what seems fair assesment of its potential market (small I'd argue) and price point (high I'd argue) it's sales seem pretty much what you'd expect.
It's how its received over time that is the critical test for something like the Go. Will the demand for the device grow or not, and will we see people switch from PSP with UMD/digital to Go?
That is the question IMHO.
Try to be reasonable... its easier than you think...