Rocketboom is a popular daily video blog. You may have to click the "archives" link at the bottom of the rocketboom web page to find the August 8 episode.
The rocketboom episode includes (in the last 30 seconds) a clip from a youtube video entitled "unicycle dance" -- some nice Japanese freestyle footage.
I can't really see clearly the female rider, but the style seems like it could be a younger Kaori Matsuzawa. The other thing I noticed is that all of the tricks are to the right, which is also what Kaori does. The very smooth riding style also make me think it could be Kaori.
