I too did IM UK in 2010, my first, and couldn't really fault it. Split transition was a bit of a pain, not so much during racking, or the race, but just collecting kit after the finish, as it had to be done that evening.
Organisation was excellent, and felt looked after, all things worked well.
Only downside, and I only have Wales to compare it against, is that with the swim/T1, T2 and the finish all being in differing locations, then there wasn't the buzz, as there wasn't a central focalpoint. In Wales, everything goes on in the same locaiton, and Tenby just feels alive during IM weekend, I didn't get that feeling on Bolton.
However, I'll probably be back in 2013 for another go