Just to confirm, I got the "unlimited, 512k" email too, sometime in the last few days.
I asked ntl for this some time back; it's absurd that someone who bust their 1Mb cap would be "punished" with a better service than the person who simply opted to stay at 300Kb.
I'm still running at 1Mb/sec, nominally; ntl say they'll "
upgrade" me "before the end of December". Here's hoping they meet their targets as well as they usually do