If you check out the DailyPaul, you will see they withstood RightHaven's attempt to sue them. If you check out Righthaven, Obama, and particularly his wife has huge connections to this firm. They go after a lot of Conservative and Libertarian sites and their owners, trying to shake them down.
A judge recently blocked a whole bunch of their attempts, citing little evidence to their case.
If you ever have any problems with Righthaven, talk to Mike Nystrom who owns the DailyPaul, he will tell you what you need to know to defend yourself from Righthaven. There are also some searchable threads on the DailyPaul about this event.
Good Luck!