Can someone explain the different card rooms?

[Barnfather]

Ok, as I have mentioned before - I really only play on 'Stars (and occasionally FT) as they are the only software clients that work on a Mac, which is my main computer.

Over xmas, I bought one of those little netbook things, primarily for the wife who can now surf to her hearts content whilst I lose buy-ins, and have installed the following clients on the machine :

Pokerstars
Full-Tilt
Party Poker
DTD Poker (had some free money from when I joined their club, so have a couple of quid in there)
PKR (Interesting way of playing poker. Quite fun I guess, but also quite offputting)

Now, I picked up a copy of WPT Poker today and it talked about 'Titan Poker' running some decent sounding freeroll satellites, and I know that Poker.co.uk have a card room - but I am also aware that many rooms are shared, with different skins.

Can anyone shed any light into the different groups of rooms? I don't want to install what are effectively duplicates.

On another note - I start work on Monday, after about 3 months off, so my poker time is going to be limited during the week from now on, so I figured I would concentrate on a few freerolls on some of these other sites rather than plough too many $'s each day into 'Stars - which is what I have been doing during my poker education the last few months

[S6TAV]

Matt when they move to the new networks do they just adopt the skins so William Hill will look like Paddy Power?

I was chatting to a friend who uses William Hill but instead of depositing money from a bank card he goes into a willy hills and buys a voucher which he then loads onto his account. I thought this was a good idea but said he might lose this option when they move to Ipoker

I could just be chatting waffle