With 78 responses so far, here are the breakdowns for the responders' favorite Lisps:
Scheme: 41%
Common Lisp: 27%
LFE: 12%
Arc: 10%
Emacs Lisp: 6%
Clojure: 4%
You can see the full report here.
I thought that Common Lisp would get more votes Scheme (isn't CL more widely used?), but apparently I was wrong. Arc and LFE have made an impressive showing for their young age (but this is probably due to the bias of my blog readers).