I find the US is generally cheaper for masses of bandwidth and diskspace on the face of it, but they oversell like you would not believe, leaving you with very limited memory. Servage for example (when I used them), give your PHP Scripts about 8mb memory, before killing it. So anything with meat in it will bite the dust instantly, meaning if your site is dynamic, don't waste your time.
One of the main reasons I use the UK for any large sites, mostly because I can send a 32gb Memory Stick (USB) to my hosting company and say "Hey can you walk the 100 yards to the cage, stick this in the USB and copy the content to XYZ folder for me please", and its done. 10gb files uploaded even off a 2mb up stream would take days constantly going.
I was recently talked into cloud hosting by James at Rackspace
Cloud Sites Pricing from Rackspace Cloud Hosting, this is certainly a viable option for anyone who wants the best of all worlds, will deliver decent speed the world over.
Edit: I haven't used the Cloud Hosting yet, as its low on my list.