O2 ran this promotion in January and have moved the Quidco back up to £70 plus a free months broadband.
O2 customers (contract and PAYG) get a reduced price of £7.34 pcm (normally £12.23)
PAYG customers qualify on a £10 top up every 3 months.
Makes the deal for a 12 month contract
7.34*11(mths) = £80.74 less £70 so £10.74
or £50.74 if you need to factor in the £40 PAYG (if you wouldn't normally pay this)
I moved to O2 and as most folks seem to agree its excellent for speed/service etc.