Couple of things:

1) Trek has a butt-o-meter now too (a friend of a friend was on the design team for their new saddles)

2) I did the specialized measurer thing and was told to buy a 143. I liked it for a while, but no more. The saddle is really uncomfortable. At first I thought it was that there wasn't enough padding for the sit bones, but now I'm thinking that the saddle is a bit too narrow. So I guess my question is: what are the chances that the size they sold me was wrong?