Both
Comicvine
and
TV Line
reports that Laura Vandervoort will be back as Kara for the final 5 episodes of Smallville.
I admit I have very mixed feelings about this, on one hand I have to say that I think Laura Vandervoort was a great choice for the casting: she got the look, the right attitude and she's able to play a strong female character without going down the "total dominating bitch" route; on the other hand I think that the produtcion team has missed so many wonderful opportunities to use the character right that I can't even start to count them.