That's what's happening according to E! Online, at least:
I for one think it could be a great move. I think she fits in very well with the rest of the cast. I still like Alex better than Sarah, though.
My only real question is what reasoning they're going to use to have Sarah around all the time. She's an insurance investigator, not an FBI Agent. Will she quit the insurance biz and join Peter's task force? Will her primary role be as Neal's girlfriend? I trust them to find a sound reason for her sticking around though, they've earned that.