With the first quarter of the 21st century coming to a close, Billboard is spending the next few months counting down our ...

and Usher releasing his magnum opus. Let's take a look back at some of the best R&B songs that were released from 2000 - 2009.

At various times in the last 20 years, an Usher Super Bowl set ... decade-spanning set of classic hits, he reconfirmed his status as one of one of pop's greatest living entertainers.