Cheers guys 470 does indeed look a good buy when you put it like that but i was already stretching budget with the £190 460, an extra £30-£60 sends me over the edge
A £190 460gtx 1gb is bad value, theres no point paying over £175 for one, they'll all overclock within a few Mhz of each other most likely. pre-overclocked ones are a rip off, plan and simple, and about 6 people have suggested that if you shop around you can indeed still find 470gtx's for around £200-210, its significantly faster than the 460gtx, the question would be, do you care, will you notice it.
The Anandtech benchmark gives a VERY incomplete picture, for instance left 4 dead, ok, its still ridiculously playable on either card at any res/setting, but you'll see that a 480gtx, and a 5970(ridiculously faster than the 470gtx with a price to match) will also get 130fps in left for dead, infact between 120-130fps the results get very dodgey, because the game becomes cpu limited there, heavily, to the point that a bunch of cards all miles faster aren't really showing how much faster they are than the 460gtx.
Anandtech has a fairly poor mix of gpu limited and cpu limited games, (ignoring the ridiculously poor layout(same game results aren't grouped together, or in order). In reality, if the 470gtx hadn't become cpu limited it might show, 160fps, 180fps, I don't know, guessing, but its faster than those benchmarks show it to be and that difference will be more noticeable as games generally get harder/tougher/slower, the 470gtx will stay much faster.
Its not a bad card in any way, at £200-210 its fantastic value, the problem is for Nvidia where its a failure, end user, its great, for Nvidia at £200 those cards make them a massive loss, bad for business, good for us.
Its hotter, and uses more power than a 460gtx 1gb, however, it uses roughly speaking 40% more power, and is roughly 40% faster, thats basically what you'd expect, keep in mind that to overclock a 460gtx 1gb to its max you'll be upping voltage, at those speeds/voltages it starts to use more power than a 470gtx at stock anyway.
Out of the two, I'd get a 470gtx, if I wasn't 100% desparate, AMD are brining out a top to bottom new range of faster cards, at worst, you get the same Nvidia card you wanted but prices probably drop to be comparable to the latest AMD cards, at best, you choose a faster AMD card that wipes the floor with the 460gtx 1gb for around the same price.
They are launching mid Oct, with availability in the last week of October so not particularly long to wait.