Here's a copy of an article that might answer your questions
[link http://www.champdogs.co.uk/cgi-bin/board/topic_show.pl?tid=10474&pg=1&msg=PstChange#62610] Pet Passport Program extends US - UK Travel [/link]
But figure on at least a year or more before any official changes.
What kind of dogs do you have? UK also has specific breeds that are banned for entry.
If you know anyone who is US military going to UK, there does seem to be a pet passport program recently in effect, but rather hush hush about it all.

There is one lab in Texas that is authorised for Titre Testing, but perhaps it is just for military working dogs.
good luck,
sara