So I don't think this is really a story, but since people are talking about it I'm obligated to comment. Mediaset are apparently reporting (say Football Italia, so this is a thirdhand post) that Edinson Cavani has agreed in principle with Chelsea personal terms ahead of a move to Stamford Bridge. But the Blues and Napoli have yet to agree a deal, with Chelsea understandably unwilling to meet Cavani's release clause and Napoli equally understandably unwilling to budge from it.
Is this a surprise? Not really, because I'm assuming what actually happened is that Cavani's representatives responded to a quick inquiry as to his wage requirements with a number that Chelsea found acceptable. I very much doubt that anything's gone beyond that -- there's certainly no official agreement there just yet. If you're curious as to what that number is, apparently it's €8.5 million a year over five years, which is right about £140,000 per week. Sounds reasonable enough for an elite striker, although the buyout clause will remain a problem.
But I don't think this represents any sort of progress on the transfer. Getting Cavani to agree terms was never going to be particularly difficult; getting Napoli to relinquish him will be. And there's no movement whatsoever on that front.