It's nice and definitely a great start!
It would look cleaner, though, if it had a tabular structure, like what you see when you run top, for example. I don't know how easy that would be to implement.
I assume that on future releases more info will be added to the site -list.
Also, is there any way that it could be depicted somehow the relationship between cloned sites? E.g. having the live, staging, and development grouped together somehow.