ying yang does get more google results, and probably searches, than yin yang, but that's largely due to the hip hop group Ying Yang Twins, rather than the eastern yin and yang symbol. You might monetize it better with hip hop stuff rather than spirituality or martial arts.
If it were yinYang.info I'd give it some good value, as I'd probably pay in the $50 - 100 range as an end user if I wanted to develop it. Many people would pay more than that, yin/yang is huge.
I think your yingyang is useable but is best for developing. Anyone who knows about yin/yang would want the correct spelling if they're dev'ing a serious site, so your name would only have value to a domainer if there's traffic, and only have value to an end user if they want a site about the hip hop group, or are developing a more informal site about yin/yang, in my opinion.
That being said, I think you might get anywhere in the x or xx range if a buyer comes along who can use it, I would think you'd at least get a few times your reg fee for it. Good luck. I did get interested right away until I backed up and saw it was a typo... so you never know
I'll bet if you auctioned it off here at NP, with a $10 start or so, you'd get more $ than through years of parking it. Different story if you develop it, of course.
