Tivo is great.  I don't watch that much TV and probably hadn't actually recorded anything on my old VCR, well, ever. 
But using time delay to skip commercials cuts an hour show down to 40 min, watching Le Tour would have been almost impossible for me otherwise, and shows like 24 almost require it.  The screens are easy to navigate and it just works.

Most of the time.

I say “most of the time” because I do have one gripe - it doesn't tell me when I'm out of room.  TiVo uses a computer hard drive to store your recordings in a digital format.  If I have 3 one hour shows per week scheduled to record at highest quality, space can fill up pretty quickly.  Sure there's ways to add extra hard drives and transfer the recordings to my PC, but for now I just want to know when it's full, and TiVo doesn't have a way to tell me.

Well, if you have the right tivo version and your tivo is on your home network, there's an easy way to find out.  You'll need your TiVo's IP address on your home network and your TiVo supplied Media Access Key (MAK).  You can download a webpage (full thread) and put it on any PC on you network.  Open the file in notepad, enter your Tivo's adderss and MAK and you're done.   The file at this download is xhtml so that means you need Firefox to view.  (I'll post about my IE friendly and ASP.Net versions soon!)
It might sound tricky, but if you already have Firefox and Tivo Desktop, it takes about 5 minutes.

The page will also show you when it was recorded, how long the recording is in time and disk space, when it expires, details about the show, recording quality, and even provides links to information about the actors, and to download the video file to your PC.  Now that's a big step up from the basic Tivo list.

Update: fixed a typo and added a link I forgot - TK