The only thing I would change is the background on the main tabs in the left sidebar, but that's just my personal preference. I like for the whole thing sidebar to have a solid background.
You refer to the title bars like 'Library', 'Playlists', Internet' etc. right?
In most of my other skins they are indeed of a solid color, but that can also make it all look a little 'boxie'
For this skin I myself really like the gradients here.
If there is any problem with readability let me know, else I'm afraid I'll keep this one to my own taste ;-)