I started tracking another Web services metric last night; the number of WS-I members. I’m not expecting this to bare any fruit (i.e. show the expected decline) anytime soon, as that will certainly lag the non-deployment of Web services on the Internet by at least a couple of years. But it’ll be interesting to watch when it starts moving.
AFAIK, they don’t have an “affiliate” program yet, which is something the more mature organizations will use to boost membership for a number of reasons (including waning interest in the space). That will certainly impact this metric if and when it happens.