Microsoft stuck a shiny piece of coal in VMware's Christmas stocking Thursday morning when it sent its competitive - hithertofore repeatedly delayed - hypervisor-based server virtualization technology Hyper-V out for a surprise public beta.

The Hyper-V beta wasn't supposed to come out until the first quarter. It hasn't changed final release though. It's still penciled for within six months of when Windows Server 2008 RTMs.

VMware, which had almost clawed its way back to $100 a share after half-real, half-imagined competition fears knocked it down to close to 70 bucks right after Thanksgiving, lost $3.23 to settle at $96.

Microsoft has been letting it slip that Hyper-V is three times more efficient than VMware. VMware says it doesn't know what Microsoft means by efficient but it does know that it's been delivering more functionality than the Hyper-V beta dreams about for the last year or two and that 80% of its accounts are in production.