I have been a pretty big fan of Verizon FiOS ever since I got it last August. The Internet has not ever gone down that I can recall, TV quality is excellent, and it's competitvely priced.
However, there are a few things that you probably don't know about FiOS, as I didn't until I spent a couple of hours of my evening playing around and on the phone with tech support.
That Ethernet port on your FiOS box? It doesn't work. Your ONT (the boxy thing that provides the FiOS magic) has a multitude of ports: incoming fiber, and outgoing coax, two phone ports, and an Ethernet port. It is not possible to use both the coax and the Ethernet port at the same time.
FiOS TV gets its listing and on-demand setting from the Internet. This has some interesting implications. I am really curious how this works if you have FiOS TV, but not the Internet plan?
FiOS TV requires the coax port. Well, duh, right?. But, when combined with the previous notes, that means that, if you have FiOS TV service, you cannot use the Ethernet port.
FiOS uses bandwidth on that coax cable from 1 to 1150 MHz. According to my router, it uses somee range under 1000 MHz for Internet service, and 1001 through 1150 MHz for communicating with FiOS TV. Note that a lot of cable splitters only go through 900 MHz, so be careful if you start using your own.
Only about half of the tech support guys were helpful when I called (one did not know several of these points when trying to diagnose what my problem was), so watch out if you need to call.