The Future is Now for Some.
There are about 1000 million PCs on the planet, most running that other OS. For the folks running free software, the future is now. They can run on almost anything. They can shift hardware/software platforms easily. They can increase the number of seats easily. The 900+ million not running free software are now or will soon be a burden to their owners: mal-ware, forced upgrades, high life-cycle costs and bloat.