One (in)famously locked lips with Madonna and Christina Aguilera on the MTV Video Music Awards.
The other famously sang about kissing a girl.
One is already a scandal-tested, 13-year veteran of the music business at age 29.
The other found success at age 23 after switching from gospel rock to candy-coated pop.
Both were performing in the area tonight, although the Katy Perry has been postponed due to illness. Together Britney Spears and Perry would have draw thousands of suburban fans to United Center in Chicago and Allstate Arena in Rosemont.
What do these dueling divas have in common?
Check out the related files link above for more.