It's better than a VCR for many reasons. 1. If the electricity goes out, you still get your program recorded (assuming it comes back on in time). 2. You can schedule it to record a certain show and it will pick it up no matter when it's on. For example, say I set it to record Scrubs always. It will notice if they switch nights and times and record it for me. And I only have to set it once and it will record it week after week so I don't have to remember every morning what to record and then try to find a blank tape. 3. The newer ones allow you to go online and set it via a webpage. So, if you're at work and hear about something good coming on in an hour, you can record it without running home. (this is assuming you have it plugged into a router or your wireless network at home) 4. It will save your shows for you until you run out of room or want to delete them. And then, if you want, you can record them from the Tivo to a VCR.
Really, it's mostly people who really love TV that like them. A lot of cable and satellite companies have their own versions of them, too, that don't require a subscription fee *and* the price to buy it. I used a fake one from my cable company and only paid $20 a month for it- no $200 - 300 right at first jsut to buy it, plus the $13 a month after that. And when I was done with it, I just turned it back in. Pretty handy.