When eBay announced their bid for Skype I did not understand their reasoning. Not from a strategic perspective, and neither from a financial perspective. The latter doubt remains, but for the first one I finally found an interesting rationale.
"I suspect that eBay’s ambition is to become the mediator of 800-number style interactions between consumers and merchants. The www.ebay.com web site is their text distribution channel, and Skype is the audio one. Each will have different sets of merchants, buyers and transaction structures. So don’t look for “eBay” functionality to appear in Skype, because they’re addressing strategically similar but functionally different needs."