I've just received an email from Amazon UK (shipping to Germany):

Unfortunately, the release date for the item(s) listed below was changed by the supplier, and we need to provide you with a new estimated delivery date based on the new release date:

"Nokia N900 Sim Free Mobile Computer with Maemo 5 Software"
Estimated arrival date: December 02 2009 - December 03 2009

Dispatch estimate: 29 Nov 2009 - 30 Nov 2009