First we have actress Shannon Lucio, who played Lindsay on 'The O.C.', she has been cast as Bill's wife Caroline, remember she's the one he didn't return to after being turned into a vampire during the Civil War. We have seen this character back in season one, and no this defiantly isn't the same actress. Apparently Caroline is a crucial factor for this season.
Next we have Marshall Allman who played LJ on 'Prison Break', has grabbed the role of Tommy, none oyher than Sam's younger brother. Year three be will delving very heavily into the Merlotte's family tree, and we should be getting some info on casting news for Sam's mother and father pretty soon.
I'm not so sure about these two newbies, but 'True Blood' has astounded us so far with their cast picks so hopefully they have made the right decision again, if not I'm sure they can be drained pretty quickly. As new info arises we will let you know.