It appears that the online Apple Store was taken offline in Europe for some general maintenance.
A quick check showed that the store was down across European territories including the UK, Germany, France, Spain and Italy. The store remained active in the US, Australia, Hong Kong, Canada and elsewhere.
However, no significant updates have been noted. It would seem that Apple is still working on the recent redesign of the online store. A number of sections linked to from the store are still not up to the same standards as the equivalent at the US store. For example details about delivery in the UK stretch to two paragraphs, while in the US the details include illustrations and much more information.