The dark satanic rumour mill has manufactured a hellish yarn that Cisco has made an offer to acquire Skype before they complete their IPO process.
The source of the rumour is Tech Crunch and it is certain that it is reliable. While it does make sense, it is difficult to stand up the rumour because Skype is on lock-down due to its IPO process and is saying nothing to anyone about anything.
However if it was true then it would cost a lot for Cisco to buy. Skype is supposed to be worth about $5 billion which means that Cisco would have to write a cheque for around that figure to be even in the ball park.
Google was also rumoured to be snuffling around Skype, but there is a small matter of angering antitrust regulators so it probably could not be bothered.