Depending on whether or not you want the home media option (which I highly recommend), as it provides you the ability to view images, play your mp3's and install HME for applications written by various folks.
Then it's just an initial setup and you are done. What I did, is pull a huge phone cable, hook it up to my tivo, go through the setup.
Once done, I then configured the network connection using a WIFI connection (over my wireless network) and from then on I just download the guide and any updates over my network, phoneline no longer needed.
It's just needed for the initial setup.
The latest Tivo update no longer requires a phoneline, if you have the home media option it will then also allow you to use your network (not right out of the box though).
What I have on my Tivo:
- USB ethernet adapter (linksys)
- Linksys wireless bridge (WES11)
So I only needed a phone line for the first setup