Skype's top expert on enterprise collaboration and communications is among several executives who have reportedly left the VoIP specialist ahead of its $8.5 billion acquisition by Microsoft, according to numerous reports.

David Gurle either resigned or was let go along with fellow VP's Christopher Dean, Russ Shaw, and Don Albert. Also said to be gone are chief marketing officer Doug Bewsher and human resources chief Anne Gillespie, as are execs Ramu Sunkara and Allyson Campa.

"As part of a recent internal shift, Skype has made some management changes," a spokesman for Skype Technologies SA told Bloomberg. The spokesman would not confirm the identities of those leaving or provide reasons for their departure.

The most significant exit, from the standpoint of business technology managers who may be concerned about Skype's direction under Microsoft, is Gurle.

Gurle is himself a former Microsoft enterprise messaging whiz who founded the company's Real Time Communications group and led the development of key products like Windows Messenger, Exchange IM, Exchange Conference Server, Live Communications Server, and Office Communications Server.

Prior to Microsoft, Gurle was global head for Collaboration Services at media and financial information giant Thomson Reuters. He was credited with developing Reuters Messaging and making it "the de facto collaboration service used by the financial services community," according to a press release Skype issued in January 2010, when Gurle joined the Luxembourg-based company.

"This is the sort of talent you would think they would want to retain," said Rob Enderle, principal analyst at the Enderle Group. "Skype is strategic to Microsoft not only for the enterprise, but also for Windows Phone 7. There's a sense that they are going to harden Skype and make it a better player in the combined space" to take on business VoIP providers like Vonage, Enderle said.

Microsoft executives have yet to provide a detailed roadmap for Skype, but have publicly said that its VoiP-based communications programs could potentially be integrated with a wide range of offerings, including Office, the Xbox, and Windows Phone.

Microsoft announced a deal to buy out Skype for $8.5 billion in early May. The U.S. Federal Trade Commission said Friday that it would not oppose the transaction. Microsoft is awaiting regulatory approval in other jurisdictions. The software maker has said it hopes to close the deal by the end of 2011.

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