Grey's Anatomy Spoilers: Major change for Valentine's Day!

One of the major female characters will be changing something about herself just in time for Valentine’s Day! Show-runner Shonda Rhimes gives us a gift with this little spoiler:

One of these three doctors, Meredith, Lexie, or Callie, will be changing her hair color to give her lover a sexy surprise for Valentine’s Day.

Unfortunately, we will have to wait until mid-February for the answer.. but who do you guys think it is?

Source: TV Guide Magazine