I still highly doubt it could cost €100 to put 16 GB of Flash memory and a Bluetooth chip in a PSP. And a 16GB Touch is $100 more expensive (it's $300, not $200, at least on Apple store) than a 16GB Nano, so the storage can't be that much of a factor in the cost.
Official PSPgo page is up on the US PlayStation website. Nothing on the UK site yet though unfortunately. The white one really does look slick as fook and I want it now.
I think it's going to have the same problems a lot of slider phones have with the slider breaking after a while. Or at least that's from personal experience...