just about every promotional photo i have seen has mike in purple and GT's press photos (what few there are) have them in white I don't like the bad juju the purple uniforms bring.
Bowls don't work that way, except the NC (and maybe the BCS games). They rotate between the tie-ins. LSU was in purple for the 2000 Peach Bowl and was in white for the 2005 Peach Bowl: So I would imagine we would be in purple again (another even year).
I will say that if GT is the home team, then I bet we wear purple, because GT is the only other school in the country that likes to wear the white jerseys for home games. So if they get to pick then we will be purple.