Today I got my black PRS-600. I charged it while I was working and sped to my computer to get started after closing time. After uploading my books, mainly free books, but three free downloads from the Sony ebookstore.
After trying to open one I remembered that I had to register the reader before getting access to the Sony ebookstore books. When I try to register at the Dutch Sony website I get the message that they are having technical problems and that I should try again later

(tried with both Firefox and IE)
I'm hesitant to try to register at the US or UK website in case problems arise in the future and Sony NL refuses to help me because I didn't register the device in the Netherlands.
Hopefully they'll fix it soon, though I expect I'll have to wait until after the weekend. Luckily I haven't bought any books yet, otherwise I would be really mad.