I wonder, though, if Yahoo might think it's too close to its brand. However, on the QWERTY keyboard, the letter "i" is far enough away from "a" to make such a TM case weak. Not a typo of Yahoo.
I would say that if you are NOT cashing in on Yahoo in any way, you should be okay.
For domain worth, you might to shoot this question over at the appraisal thread.