IMO has confirmed that Microsoft is blocking access to Skype preventing them from connection to their instant messaging platform.
Microsoft recently merged their Live Messenger and Skype platforms so to connect to Live Messenger as well, you need access to the Skype platform.
Unfortunately, Skype blocked us and we can’t do anything to fix it. If you would like Skype back on imo, please email them directly. Thanks!
— imo messenger (@imoim) May 30, 2013
Skype of course has apps for multiple platforms but no web access outside Outlook.com without a plugin. This alone ensures that devices like Chrome OS completely lose access to Skype because of the platform limitations.