I don't think it's the Linux users who will run, but rather that Microsoft will eventually decide that Skype on Linux doesn't help them cling to their "fat client" business model. One day soon, they are going to come to the realisation that they are sad on the "clinging to an outdated business model" front as the RIAA/MPAA. Then they will "trim the fat," "reorganise" and "adjust the company direction." Which doesn't actually mean what it's supposed to mean.
Instead, it means they will litigate like mad, expend quite literally billions of dollars trying to make using anything that isn’t their outdated business model illegal, flail around and generally piss into the wind for about a decade. Part of this will be pissing away yet more bore billions of dollars to do nothing more than try to thwart other companies whose business models adapted and whose thinking processes aren’t antiquated.
Eventually they’ll spiral the drain quicker and quicker, selling off pieces of themselves and giving huge golden parachutes to their few remaining executives before finally becoming a footnote in a textbook somewhere as the shrivelled carcass is bought by someone else for nothing more than their patent hoard.
Just like so many others in the IT world who couldn’t adapt.
Linux is the EMENY here. They aren’t going to get support from Microsoft. They can promise everything they want, but eventually Skype will be passed off to someone who sees Linux as a direct threat to a business model that should have died half a decade ago, and it will be taken out back and shot.
In case you hadn’t been paying attention, Microsoft is in a “death spiral.” The lynchpin to their entire empire – the integration of Office into absolutely everything – is slowly becoming less and less critical. Their competitors are building “good enough” stacks of products that are not only integrated, they are multi platform, require a tenth the resources and work entirely through a browser.
Microsoft will take a while to die, but – barring a miracle that gets rid of Ballmer – die they will. Companies in death spirals do not offer support for rival platforms.