Because when it comes to rumors, if given A and B then one must find a way of making them simultaneously true. Special prizes are awarded to the people who can string the most incongruous rumors together based on the most insignificant details of each.Uh, what does WWDC have to do with the release of Leopard? They're two separate things. Tiger was released in "spring" 2005 (late April), and WWDC'05 was also in "spring" 2005 (early June). The presumption has long been that, like two years ago, the new operating system would be available long before WWDC. There is nothing to contradict that as yet.
Apparently, Leopard will ship only with a grey calendar app and a cool cosmic theme...