I've been on VoIP for years now. I haven't had a POTS in 4 or 5 years now. It's hard to beat clearer calls, free long distance in North America, and web access to call display (incoming and outgoing). [Hard for the teenagers to abuse the phone.] I can forward my phone to any number through a web interface. I have a virtual number that rings to the same line as the main number -- relatives in a far off city can call me for free.
Other folks ask me about 911 if the broadband goes down, I tell them everyone in the house has a cell phone!
If I go on vacation, the phone can come with me, provided I have broadband hookup there.
All for the same price as POTS.
Limbic~Region mentioned rewiring the house. Why? I got a cordless base with multiple satellite handsets.
I'm hoping the video will go wireless soon, so I don't have to run any cable at all.