The Personal Anecdote: Back when I used to play this Mage, he was specced Frost, for the survivability. After Cataclysm hit, I decided to try out the starting-area for Gnomes and also see what playing a low-level Mage is like. So I made a Gnome Mage the other day, and ran him up to the mid-teens. I went Frost, and found out-- I didn't really enjoy having a Water Elemental. Aside from the obnoxious noise, he had a tendency to stand on top of my character or otherwise obscure my camera, since he's so much bigger than a Gnome. And I don't care that much about playing another pet class (I have a Hunter and a Warlock).
The Bottom Line: I'm willing to try out whichever tree seems to be best for solo-leveling a Mage. Even if it's Frost, I can work with it. Is there a clear answer as to which tree is best to spec in for my purposes? If not, what are the dis/advantages of the three trees for soloing?
THANK YOU for your help!