The new Roxio Toast 8 essentially has Tivo Desktop built into it. Tivo had been screwing Mac users for some time, saying over and over "it's coming, it's coming," in regards to a Tivo Desktop equivalent for Mac. I think they finally just decided to have Roxio build the software because they realized they'd never get to it and their users were just getting frustrated.
Toast 8 allows you to download shows, watch them on your Mac, covert them to iPod compatible format as well as burn them to DVD. It's pretty sweet! Downloads and burning take a while, but that's to be expected (they're large files).
http://www.roxio.com/enu/products/toast/titanium/overview.html