Please Help - Power Loss

I'm having a problem with my tahoe. It usually happens right after start up, and tends to go away after a bit of driving, but not always and not completely. When I first start her in the morning I'll give it a bit of gas, but the truck just bogs down and barely goes anywhere... It feels like the computer is either dumping a bunch a fuel or pulling a bunch of timing, or both... Eventually it'll snap out of it and slowly begin to pick back up like normal, but it still feels like I'm driving around will a bit less power than normal... I'm thinking O2 sensor or something along those lines.. Anyone have any ideas???

Check your PCV valve as well as the Exhaust Gas Recirculation (EGR) system and Evaporative Control system purge valve.

Also check your fuel system for impurities (dirt, rust, etc.) and consider changing the fuel and air filters.

Well, I solved the problem, but I'm not quite sure what it was exactly. Here's what I did: Installed new battery (old one had a leak), Cleaned MAF wires, put in higher octane gas, performed ECU relearn process after battery install...

The problem hasn't happened since...