RG-11/U is 75ohm and is usually triple/quad shielded and typically has a maximum attenuation of 3.65. RG-213/U is common form amateur radion and is 50 ohms and is single shielded with about a 5.95 attenuation.
http://wiki.answers.com/Q/What_is_the_difference_between_rg6_and_rg11"
satellite cables and TV cables are the same to a point. the difference in the too are is the TV cable a RG59 or a RG6 RG59 will not work with satellite because if the smaller center conductor with satellite it pushes power were it will end up destroying the center conductor RG6 witch is in newer homes is ideal for both satellite and cable RG11 is used with TV cable from usual the box / tap outside to houses usually running over 300 ft depending on the DB coming from the starting location
VoIP cables are RG11 for phones lines and UTP RG45 for internet connection.
Go ahead and re-wire away! Your biggest problem might be in finding end connectors that'll fit the RG-11. Otherwise, it's 75 ohm cable and compatible. dude rg-11 is way over kill that is primarily used for drops that are over 200 feet long.you would be fine just using rg-6 cable because it would be alot eaier to use behind your wall plates.