I have to admit that there's not much about the Wordpress interface that I like, but they do have a kick-ass login screen.
It's clean, it's simple and most importantly it's direct. My favourite part of the process is the feedback mechanism for entering your credentials incorrectly. The login box shakes bake and forth on the screen like a dog shaking water from its back. Afterwards a very concise red alert box appears above it.
I just wish their simplistic login philosophy transferred over to their administrative processes. Thankfully this blog is hosted on Squarespace, a company that revels in streamlined interfaces.