From the Winter TCA press conference in CA: http://www.deadline.com/2012/01/mariska-hargitay-to-continue-on-lo-svu-harry-honnick-jr-joins-for-arc/
SVU star Mariska Hargitay... will stay on the show beyond this season, Greenblatt said. Mariska is not leaving SVU, Greenblatt said.
Hargitay confirmed that in a pre-taped video. I'll be back, she said. I can't leave this show, I'm having too much fun.