I'm not sure if the sock method can give anyone 100% certainty but having a buddy with a spare MAF to swap should be your next step.

I've been following this thread because my car is acting the same way. Let us know if your MAF is bad when you find out. Swapping a MAF is easy stuff, but if this doesnt work you might look into cleaning the IACV, which can be a bitch (unless you have little hands like that guy on the Burger King commercial, LOL!!)

http://www.youtube.com/v/xu_bE7g2wqM...</param><param