Twitter is not only down most of the time but their funny downtime messages are even more annoying. Its been 3 days since I last saw the twitter@twitter.com bot present online on my gtalk. I don't know whats wrong with them and I don't care to investigate. And no I don't think Pownce cuts it as a simple communication and micro-blogging tool, its way too complex and convoluted for simple twitter like usage. Shall wait for a reasonable twitter replacement to come up.
Here is my small list of features which I would retain and junk the rest.

1. An embeddable widget for Blogs which shows your micro-blog/sidenotes you and or with your friends sent to this new service.
2. An RSS feed of the above two
3. A Jabber bot that you can add to communicate with from any Jabber messaging service like gtalk, jabber.org etc.
4. Compatibility with existing twitter clients.
5. SMS/E-mail integration. E-mail integration can maybe use a strategy of using a unique but changeable guid in the subject line as a spam avoidance technique for auto-approval of messages.
6. A simple configuration page to follow and approve followers, configuration for IM/E-mail GUID/Mobile.

Drop me an line if you are interested in developing this application.