Witter 0.3.0 is now in extras-devel.
see http://danielwould.wordpress.com/witter
for latest changelog
main point is that if you don't need multiple account support, it's probably safer to not upgrade just yet. lots has changed to underlying code with the only real external change being that you can now run multiple accounts.
That said if you do use identi.ca or multiple twitter accounts, or any other twitter compatible account, I'd be interested in feedback about the way it's done in 0.3.0