Hi m@dman,
There are no PVRs currently available that will "eat the Telewest feed" directly, as you put it (great way of putting it, by the way!) Telewest are currently developing a PVR which will connect directly to the network, but I don't know how long it will be before that's launched. The Freeview PVRs that are available aren't easily modifiable to take a cable feed as the digital signal is different (DVB-C as opposed to DVB-T).
No new TiVo PVRs have been manufactured for the UK market for a while, since Thomson stopped - but I still have two connected to my ntl boxes, and they work VERY well. Far superior to Sky+ (which my parents have). They will also work with Telewest boxes.
They are still available via eBay, and you can still sign up as a new subscriber to the EPG service by calling the telephone number in the manual. There have been recent rumours that TiVo are planning a return to the UK but as yet, nothing has come of them. What you heard about DirecTV is not quite correct - DirecTV used to offer a satellite receiver with TiVo technology built in, but have recently dropped this in favour of their own in-house solution. This is similar to the UK situation, where Sky did the marketing and back-up for TiVo before launching their own solution. Sky still operate the UK call centre for TiVo. TiVo are not owned by DirecTV.
There's loads more information available at
TiVo's UK site and the
TiVo Community Forum. Hope this helps!