I spent a bit of time fiddling around with an undergeared mage to see which frost heavy specs worked nicely for leveling 60-70. I found that straight deep frost was nice but didnt really have very good mana management: I had to drink every two or three fights.
Then I started to use:
Talent Calculator - World of Warcraft
as my template for frost and placed the remaining points to the arcane side (in particular for clearcast and magic absorption) with the objective being to reach around here:
Talent Calculator - World of Warcraft
I dabbled briefly as full arcane which was definitely nice - they fixed the previous mana management problems and the instant cast arcane barrage there is pretty nice (something you can cast while running like mad from the mob you have slowed!) Anyone else fiddled around? What do you think?