74.8 million people read at least one romance novel in 2008.
The core of the romance fiction market is 29 million regular readers.
24.6 percent of all American [sic] read a romance novel in 2008, versus 21.8 percent in 2005.
29 percent of Americans over the age of 13 read a romance novel in 2008.
Women make up 90.5 percent of the romance readership, and men make up 9.5 percent.
The heart of the U.S. romance novel readership is women aged 31–49 who are currently in a romantic relationship.
Pop over to the Readership Statistics page of the RWA website for more information on today's romance readers, including purchase behavior and some surprising tidbits like this:
45.1 percent [of survey respondents] were not aware that authors receive no royalty payment for the purchase of used books.