[RedsBaron]

While Faith Hill has claimed she was joking, it sure doesn't look like it from that clip.
Even though Carrie Underwood has sold a lot of CDs this past year, I think in country music there has been historically a bit of the attitude about "paying your dues." As a newcomer, Carrie Underwood may have been perceived by some of the more veteran performers as not having paid those dues. The attitude may have been one of "give her the Horizon award, but let her wait her turn for the Female Vocalist" award.
Faith Hill had a huge year in record sales and ticket sales this past year as well, and she is more of a headline act than Carrie Underwood. I very much doubt that Faith would've been ticked off had Sara Evans or Martina McBride won. Sara has never won the honor (nor has Shania Twain for that matter). Faith has only won the CMA Female Vocalist honor once. Martina is a four time winner of the award and I doubt Faith would've been upset if Martina had won yet again because (1) Martina is the best female vocalist in country music, bar none, and (2) the McBrides and the McGraws are reportedly good friends.