I was a skeptic of Frost, as I've only ever played Arcane since The Shattering and when I finally did spec and play Frost, I haven't looked back since. Also, if you have great pet control, dropping that extra Nova is no problem, because your pet is more prone to dieing when it is at your side, than it is a safe distance away (I've noticed at least). Like someone above me said, keep your pet on passive at all times. It's only ever needed to drop the extra Nova anyway. The only time my pet will attack something, is if I use my macro I made that is coupled with Frostbolt. Waterbolt doesn't do much at all tbh, averaging about 17 a hit, but it's nice additional damage.
Survivability is great, with the added CC's (the introduction of Cone of Cold, the pet Nova, possibly specc'ing into Imp Cone of Cold, etc). Damage output is alright. You're obviously not going to burst stuff down (Unless you want to and spec into Shatter), but Frostbolts hit for roughly 200+ and fireballs a little higher than that, but not by far.
This is a macro that I use. Again, it's not game changing or anything like that, but it does make your pet that much more useful than just another CC.
#Showtooltip
/cast Waterbolt (It may be Water Bolt, I cannot recall)
/cast Frostbolt