Allmusic used to be one of my favourite search engines - dedicated only to music, most things cross-referenced and decent bios. Now, after a redesign of the site it is almost impossible to use: it's slow, poor support for non-IE browsers, the links don't show up that well (you tend to click everywhere in order to find the links), and, simply, it's not as intuitive as it used to be. I hope they will work it out.
A nice detail though. They try to use the visual search Thinkmap which is incredibly neat and smooth. You have to try the dictionary at Visual Thesaurus! It would be a real killer app if allmusic were able to use Thinkmap to cross-reference all music, from bands to similar bands, from songs to recording bands, etc.