Digium recently released the final version of the module for integration Skype and Asterisk. The implementation is done as an add-on channel driver. The module allows to Skype-to-Skype calls as well as supporting SkypeIn and SkypeOut. Additionally it offers set and retrieve online status, trunk calls between Asterisk servers over Skype, make and receive multiple concurrent Skype calls from the same Skype account. The price of Skype module for Asterisk is $66.00 per channel.
Personally I don’t see a big advantages of Skype over the SIP gates for voice calls. The SIP gates are cheaper and they give better voice quality. But the Skype module for Asterisk can be very useful in case of calling directly to the Skype accounts since Skype is a standard de-facto for business communications. In any case it’s good to have more choices for VoIP calls!