Where is Frank Oz?

What happened to Frank Oz? The last few muppet projects have used other voice actors instead, and I really miss franks unique style (ie the way piggy moves)

Frank are still working with the Muppets. But he has scaled down on his work with the muppets, mainly because the lack of time. His main focus is his director jobs.
But he does some segments in the new episodes of Sesame Street from what I've heard.
Actually most of Franks characters have been recast to Eric Jacobsen, so it's not a voice actor but a new puppeteer.

He's got a new movie coming out this summer - The Stepford Wives. You see the trailer here.

Frank Oz is a busy man.