another burning oil question

180,000kms on motor had it on the road for 2 months this yr so far and i go thru a quart of oil every 2 weeks, I know one of my headgaskets is going bad on me(looks soft and moist in one area, not leaking yet), car is not leaking anything on my driveway, anyway im just curious wut the odds r that its my intake gasket/head gasket/other gasket or if it is indeed more than likely my piston rings in that case a rebuild will b around the corner shortly.

Also I smell oil when im in high rpms and my friends behind me notice black smoke coming outta my exhaust when I downshift and WOT.

I read other threads but didn't really help me out much.

Thanks!