No they didn't invent aesthetics. It was more just an observation e.g. the icons from the old taskbar are bigger and are beginning to resemble OSX's dock. There's a lot of healthy blogging about this, here's just a couple:
http://www.osnews.com/story/20613/Is...Like_Mac_OS_X_
http://advice.cio.com/shane_oneill/w...sembling_a_mac