Listen, HTPC, people... You're right. Tivo isn't for you. BUT, not everyone wants to set up and maintain and use an HTPC.
This Tivo IS for people that want to replace their cable company's awful HD DVR. With FIOS, the HD DVR will cost you $20/mo (PLUS a $40 "upgrade" fee if you want the latest one!), and is generally not very useful.
With the Tivo Premire you get a smarter DVR. Even if you have more than two shows you want to record, the Tivo will record the two it can, then figure out what episodes it missed of the other shows and record them at a later time... Big deal if you have 20+ season passes like our household! Plus, the season pass management is way easier to use than the FIOS DVR.
PLUS, you get access to all the online services... Your Netflix streaming, Hulu/Hulu Plus, Youtube, Amazon Rentals, etc. So it kind of crosses over into the Boxee/Roku arena...
Now, the down sides. Yes, there's a monthly fee and a CableCard rental. But for me that actually ended up being $2 per month cheaper than the $20/mo rental fee for the FIOS HD DVR. Also, some cable companies use technology called Switched Digital Video which will make some channels not work on Tivo boxes. But all you need to do is request an SDV adapter from your cable company. They're free. Also, you miss out on any of your cable company's "On Demand" stuff. But to be honest, we never used it on the FIOS DVR so we don't miss it.
Lastly...the setup. I have never had trouble getting my CableCard and Tivo to play nice. I go to my FIOS office, pick up a card, they activate it at the store, I take it home and put it in the Tivo. Then you go online and put in the activation code. Done. I've had more trouble with techs that have no idea what a CableCard is or have never seen a Tivo... So I follow the directions and do it myself. Once it's set up there is no maintenance or anything. It upgrades itself and downloads the guide info automatically. You never have to touch it again unless you switch cable companies.
So yeah it's not for everyone. But if you hate your cable company's DVR and you want a set top box with some online services built in, this is your jam.