Here's what led to her flipping-off the host.

During the news today, Kat Mykals was filling us in about drama that went down at U.K.'s Brit Awards, which is sort of like the British version of the Grammy's.  Adele won the premiere award for 21 as British Album of the Year.  Shortly into her acceptance speech, she was cut off abruptly by the host of the show, who apologized and quickly pitched it to the band Blur.  This led Adele to flip off the host of the show, which Adele admitted later was a message to the "suits," not to the fans or the award.

 

Here is the video.  While I understand the pressure and stress the producers feel putting on a live show like this, I think it was in poor taste to cut Adele off so quickly.