If the claim that the Linux client is no longer able to join calls is true, I think the Skype team really needs to respond.
Microsoft has been doing all sorts of cool things lately and it's odd that the Skype team hasn't been a part of this movement toward a modern, multi-platform world.
In my little corner of that world as the owner of an agency which spends money on Skype credit every day and uses Skype for a healthy part of our business communications, if Linux users start having trouble connecting to calls we are done with Skype immediately. There are enough alternatives out there nowadays that we will drop this tool.