Wolf, is a freakin' BEAST in the air. Easily his strongest point in the game, the Bair's range is insane, and you can do ANYTHING afterwards, since it has so little lag. When they say Zero Lag Fair, they MEAN IT. You can do anything you could possibly imagine.
Even against a shielding opponent. Even one frame of shield stun is one frame of an advantage for you. You could easily spotdodge and punish for those shield grabbers. Good Lord, Wolf is AWESOME in the air. His horizontal movement is NEARLY ON PAR WITH WARIO. The only reason you don't notice it is because of Wolf's fast falling rate and Wario's much slower falling rate.
Proof:
http://smashboards.com/showthread.php?t=167952 It's on SamuraiPanda's list of helpful threads.
With Bair and Fair being nearly lagless, it's hard to punish Wolf, with a nearly lagless spike you can approach with and spike people... Dair is Wolf's laggiest aerial (assuming you can AutoCancel Fair)
Nair is freakin' awesome, granted not a very good approach in front of them, but if you get on top of them or behind him (With Wolf's absolute win horizontal DI) it makes a great approach, it has excellent priority assuming the hitbox can hit them. It cancels out almost ALL PROJECTILES. Including Snake's Mortar, TL's boomerang, Zelda's Din's Fire. Good Lord...
Also, Bair + Fsmash = To quote a good Wolf player... "A gold mine" You can throw out so many tricks with this. If you just stay out of range with your Bair, they let down their shield to punish... except, they get a face full of Wolf's FSMASH. So many tricks can be used with this combo. His Bair is an excellent move, he can use a Wall of Pain with the Bair...
Who said that his air game wasn't his strongpoint? It's definitely not the easiest to catch onto, but a really good Wolf player told me "The more you're in the air, you'll find the more you'll win."
To sum it all up: Wolf simply OWNS in the air, his only downside would probably be the range of his attacks (Though Bair has EXCELLENT range) and maybe priority. Not to sure about the priority part xP I'm assuming that the people that say Wolf lacks priority are comparing them to MK's aerials... not to sure though.