I just posted this elsewhere in the forum. Seeing as other seem to be having the same problem as me I thought I'd better post this here as well:

I bumped into a problem with witter. I'd forgotten to configure OAuth and witter just hung on startup when trying to retrieve my timeline. I've posted a bug report about this.

If anyone else bumps into this problem I solved the issue with witter hanging on start up by opening xterm and typing:
You then have to setup your twitter account details again making sure that you configure OAuth in the account setup screen.