CMA's

Kellie looked silly

I'm with loveshorthair on most of these. 

Either Kellie Pickler is right in the middle of the awkward "growing it out" stage, or (which seems more likely given her history) she chose weird extensions.  Like her long, like her short, but this just looked funky.
 
Carrie Underwood's hair was too blonde and, when she wore it loose, so layered that the ends were thin and straggly.  She looks great in long hair but needs a healthy trim.  And some of those outfits--that white baby doll number in particular!

Another bust for me was Nicole Kidman.  She looked as though she had a hank of  blonde dynel  glued to her head.  Whatever happened to the gorgeous red curls? 

Martina McBride is great long or short.   Lee Ann Womack also looked terrific with a very simple hairdo.    Taylor Swift's updo  was a little unusual for her but it looked cute.  (Did you catch the crack about leaving early to take her math test and then meet with her accountants?)

I thought Reese looked great and I  prefer Martina with short hair.

I agree rardman, Martina never went short enough for me.  I too like her better with long hair.