To my eye, the basic thrust here is "eye candy" and non-uniformity / inventing new standards.
1. Eye candy -- the cyclist graphic is perhaps cute, but the flat-handlebar bike with cranks and pedals has been a standard MUTCD sign for a long, long time. How long would it take for motorists to catch on that the new graphic meant the same thing as the old one?
2. Non-uniformity: MUTCD has specific rules about which sign colors go with what signage purposes, and blue as a background color is supposed to be reserved for "motorist services" or something like that. I'd say stick with green instead of blue, promotes (subtly) the message that bikes have same rights to road that cars do.
3. These folks are about a year or more out of synch with proposed revisions to MUTCD -- issued early in 2008 for 6 months of comments, now being reviewed, for a re-issue / update in 2009. Unless some of these were sent in as comments, I wouldn't expect to see any of these suggested signs used anywhere that MUTCD reigns.
JRA's avatar would be better than the suggested cross-pollination of the Olympics's cyclist with a motorcycle helmet ...