Pull your intake pipe and look inside of the Throttle Body. Mine is covered in oil. The intake tube has a smaller tube just before the T/B that vents the valve cover. High revs are causing some of the oil splashing around in the passenger side head (well, probably it is sucking in oil MIST) to get sucked into the T/B and burned in the cylinders.
Just keep an eye on your oil level and top it off when it gets low. If it REALLY bothers you, you might want to do a search for "Oil Breathers" and try that out.
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