I ditched Sky a couple of years back and went to BT Vision.
For a family BT is pitched right. The main pack costs £7.50 a month and gives you a Freeview 2x simultaneous channel recordable PVR plus 20 "premium"channels including discovery+UK Gold+Nat Geo along with various catch up TV options, plus BT sport free. £3 a month gets you numerous kids channels another £3 gets you the premium channels and sport in HD and £5 gets you the on demand film and box set library which is quite extensive has a lot of content from channels not in the 20 premium channels (and is what we watch most as were not tied down to programme start times)
All in my selection is £18.50 a month for more channels that I can shake a stick at plus HD live FA Cup and Premier League football. (and can subscribe to Sky Sports on a month by month basis if I want to)
Sure, if you are a sports fanatic, Sky can't be beaten but for a family where everyones at work or school 5 days a week and the TV is tuned in to CBeebies or Childrens BBC half the time, sky is just not value for money.
Skys problem is that their entry packages are just too expensive. The £21.50 Sky entry level "original bundle" is much what you get with BTs £7.50 package, but some of the 35+ "premium" channels are actually free on Freeview like "Dave", "Really" and UKTV Drama, and it dosen't include Nat Geo and Discovery, you have to pay £28 a month for those. And then theres still no free premier league football chucked in.....
Skys Broadband is abit cheaper than BTs but I'm with BT primarily for a good quality 40Mbit unlimited fibre broadband that is reliable, supports VPN to work and dosent throttle you when lots of users are on in the evening. Sky is only £3 a month cheaper at £20 than BT at £23 for this.
Sky are good, but alas in my experience too expensive unless you have the time and inclination to spend several hours a day watching TV, want to watch Skys own entertainment channels or have a fanatical/specialist interest in films or sport.
BT, for all their faults, are giving Sky some serious competition, and Mr Rupert a dose of his own medicine.....