Welcome to Charlottesville!
There are lots of local trails listed on
http://cambc.org/rides.php. They are all good stuff. People probably mostly ride Walnut Creek, then OHill, simply because they are very easy to get to, relatively easy to navigate, and just a ton of fun.
Of course, no one is really riding on any trails right now because they are all snow covered and it's just impossible. Even when the snow melts, we all need to be careful not to ride wet trails. Have to let them either dry out, or freeze.
-j