From the national bicycle dealers association website.
2009 sales all wheel sizes 14.9 million

mountain 27.8%
comfort 10.3%
hybrid 20.4%
cruiser 3.3%
road 700c 14.9%
youth 21.3%
other 1.8%

I assume recumbents would be part of the 1.8% others.
Road bikes weren't near the top of the list either.