We just pushed a new release (Build 54, r21895) to all non-alpha users.  This release is a small patch, which adds support for a change in the Facebook chat protocol that broke login.  This will be fixed for alpha users in the next alpha release we do shortly.

If you experience any bugs please use “Help > Send Bug Report” in the main menu to submit a diagnostic log or email us at bugs@digsby.com. If you have any suggestions, please email us at features@digsby.com.