Microsoft's slog tactics [1, 2, 3] against VMware [1, 2, 3, 4] are accompanied by Microsoft's increasing control over VMware's management (many Microsoft executives have entered it). VMware employees are complaining as the company turns its back on Linux, but it does not mean that Microsoft is an ally of VMware; the same goes for Citrix. They just all work together to advance their own separate interests rather than compete properly. it's the illusion of competition, almost a collusion.
VMware says Microsoft 'shenanigans' led to new VMworld restrictions
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One year ago, Microsoft handed out casino chips directing VMworld attendees to a Web site titled "VMware costs way too much." At the time, Microsoft was a "gold sponsor" of VMworld. But at this year's show in San Francisco Microsoft is no longer a sponsor and claims that new VMworld rules prevent it from exhibiting the latest version of System Center Virtual Machine Manager on the show floor. Citrix has made similar complaints.
--Microsoft's chief evangelist