oh yes dont forget quidco or topcashbask. Sky BB sometimes do good deals through that.
I tend to avoid PlusNet as they have stupid limits like 10Gb, 20Gb etc per month on most of their tarriffs and their unlimited tarriff is expensive compared to Sky BB.
Not sure what Talk Talk is like although I do keep reading horror stories about them. Maybe someone on TalkTalk can comment.
Talk Talk is generally good only if you don't run into problems. Broadband is more or less same like any other provider as it is on BT line, you get nearly the same speed.
I like talk talk more for their nice and cheap features on home phone!! On talk plus package (which now come with tv which I don't really care about) gives you free unlimited anytime minutes to 0845 which is very good. Also they give you calling features like 3-way, call wait, call forward free of cost.