Agree with a lot of the above- especially the rake on party, but still think party worth a look- they regularly give you free cash to play with (if you win, great, if you lose, wait until they offer more free cash!)- best promos of the european sites.
Titan is my favourite (if you have the right affiliate...) ipoker site, though also enjoy CD poker as I have a $1k private freeroll there every week..
32red, GNUF also good (microgaming sites)
or luckyace are pretty easy to win on...
depends on how much you play, what your bankroll is and what you play (sngs/ mtts/ cash games- pl omaha or nl or limit?)
Have about 20 sites but still think pokerstars
and fulltilt are the best 2 (pokerstars have amazing promos for uk players going on)
bonus/ fish- luckace/ 888
- gnuf/ fortune (luckyace $5k this weekend as well)
promos- party/ 32red
There are loads of the ipoker sites
to clear bonuses on - william hill, tony g, cd poker, poker ocean, pokerducks, ladbrokes(?), bet365, paddypower- and sure many more- know titan is the biggest of them though, so able to offer best stuff