According to Skype's blog, a whiteboarding feature was added in Skype 3. Using Skype 5 on Windows, I can't find this feature. Is it present?
Skype used to include a Sketch Pad out-of-the-box (available under the
Do More menu). Then it became an extra that you had to download via the Skype Extras Manager (
Tools / Extras / Get Extras). This feature is gone as well.
Now you can use IDroo. It's an external application that integrates with Skype.