Dislike: There’s no sign up, only a Login with Facebook button (which is annoying personally because I don’t like logging in with Facebook http://screencast.com/t/hsKqMkyuR.)
There’s a bunch of white space to the right hand side of the page (http://screencast.com/t/2swhK5EPb2i), which makes the page unsymmetrical and doesn’t feel right.
I don’t like how most of the things on the page don’t have any description beyond an icon. I know most frequent internet users can probably figure it out, but it still requires me to think for a second to make the associations (http://screencast.com/t/6E2ydk3kh) and some older users and perhaps not as savvy internet users may not understand it at all (albeit the site might not be aimed towards them.)
I know this site is for people who like Essential Mixes, but I have no idea what a collection, Essential Mix collection or FACT collection is. Adding a description could add an unnecessary element while removing a confusing aspect, so its up to you to make the choice. I think a description can be made (without hurting user experience) by adding a disposable box next to the collections briefly explaining what they are.
Some specific aspects of the design I don't like (misalignment, pixels off center, etc.): http://screencast.com/t/1Tg9Fo75xo3
Hope you don't take my thoughts negatively, just trying to help. Overall I like the site, its is simple and has no truly unnecessary elements, that’s good. Also, I like this touch http://screencast.com/t/oWFv5kkU2), adds to the user experience. And I like how easy it is to play songs (just click and it starts playing http://screencast.com/t/MwkkU8musZ).