In this telling article, we learn that they have only sold "a few dozen" cars. And, better yet, new sales are on hold because they need a waiver to sell highway vehicles in 2012 that don't have stability control. Apparently, Wheego didn't have budget to develop stability control the first time out.
My only interaction with Wheego was sitting in a Whip demo car at a local ex-Chrysler dealer, which has since gone defunct. The ex-Chrysler dealer struggled mightily to sell Wheegos, but couldn't move a single one.