I had Tivo a decade ago, and really liked it. But it was pushed off the market here in the UK. But now it's back, and I got mine today. I can't believe just how much superior the box and service is to the standard virgin cable box (even on + service). It's awesome. Just the Search functionality alone is worth it, and then comes how it learns your taste, etc.
(Even if the cable box had worked as intended, it would still be way inferior, but it was so incredibly buggy and unstable that I was really happy to get rid of it.)