haha from your descriptions it sounds funny..
My friend who LOVES Ayu and SHE said that SHE's new song "星光 (xing guang)" doesn't even mean the same thing as "About You". It's about "friendship". The lyrics aren't the same, so, all the similarities are just a bit of the tune, I reckon. When you think about it, there's a lot of tune/music copying in the industry.
Fans will be fans~