Microsoft has confirmed that the Skype app for Windows Phone is scheduled for late 2011



From WPCentral:

Last we spoke of an app for Skype coming to Windows Phone was back in April, at MIX'11. An app was demoed and was slated for a "late fall 2011" release. Neil Stevens, Skype's Vice President and General Manager of Products and Marketing, spoke about how Skype is looking to be more integrated into the OS as opposed to being a mere app, which should be likely with Microsoft's acquisition.

  Skype for Windows Phone still coming this year