Facebook is perhaps the most obnoxious company I know of in terms of UI and UX changes. The interface is constantly changing, they introduce bizarre functionality, and the site is so buggy that I wonder if they have any QA people on staff.
The latest change that makes me long for a competitor to rise up and send Facebook the way of MySpace is the integration of e-mail messages and IM. They are now one and the same. IMs are automatically cataloged in my inbox as if the chat had been an e-mail conversation. E-mail messages appear in IM the next time I chat with that person as if it had been a chat.
I don’t like it. I don’t get it. I want my e-mail and IM separate.