Many people think the "pop" category means, NSYNC and Celine Dion music, but the "pop" stands for "popular" and that includes all that is popular.
That's why Tony Bennett, Frank Sinatra and Doris Day have all been considered "pop artists" over the years. It's why songs like ACHY BREAKY HEART, DEAR MR. JESUS, BUTTERFLY KISSES, Whitney's version of the STAR SPANGLED BANNER (during Gulf War) and even the instrumental version of the TITANIC THEME have been "pop" hits over the past decade.
It's also why "pop" radio stations, tend to play everything from Nsync to Nelly to No Doubt to, yes, Norah Jones.
Again, the key word is popular.
Jazz is back, baby!