1/2 quart on synthetic oil in 6,000 miles over the course of one year on a motor with 130k miles.. I'd say thats pretty good.

Personally I'd test the compression on those cylinders when you put new plugs in, that will give you an idea of how much blow by you've got if you think thats where the oil is going.

Those plugs look pretty normal as well.. <img src="/forums/images/graemlins/kewl.gif" alt="" />

1999 Mitsu Montero - Crappy Weather
1992 Isuzu Pickup - Zombie Apocalypse
2008 Saturn Sky Redline - Nice Weather