Mage build advice sought

[Bob the Beholder]

You used the past tense in the sentence about your build. What spec do you use now?
Edit: Technically I believe the tense in question is past progressive, but the implication is that it is the build no longer used.

Sad as it is, I'm currently frost, 17/0/44. (Especially sad when considering I'm a Spellfire tailor.) I'm a big PvPer, and as much as I just love lighting some poor fool up, I am having trouble giving up the greater control and survivability of frost. I maintain, however, that for the purpose of levelling, arcane/fire is the way to go.

*edit*

As to your latest build, it is pretty solid. My suggestion would be to free up a few talents points in the early tiers of the arcane tree to be used for Arcane Meditation and Arcane Mind. Minimizing downtime goes a long way to speeding grinding. Dropping Iimproved Arcane Missiles, as mentioned earlier, is a pretty good candidate for coming up with those points. It's useful, certain, but with this build you're going to be having a scorch with a high crit rate, high mana efficiency, and decent interruption resistance already. IAM is mostly unnecessary. A matter of choice, certainly, but it's my opinion you can lose it without hurting anything.

Another thing I would suggest trying to free up points for is Incinerate. Scorch and fireblast will be a staple--and like I said earlier, with the buffs to crit damage you get in Arcane, buffing crit rate as high as possible is something I would suggest you shoot for.

Last and final suggestion for this build--improved Scorch. Scorch is very nice for this build--you're likely going to be using it quite a bit towards your later levels. It's likely you're going to end up with a few stacks of this on a lot of mobs, and it can make a difference. Very useful for instance boss fights, also.

For those last two talents, though--incinerate and Imp. Scorch, you'd probably have to give up impact to free up the points for them, which is a rough choice.