Given that they are deprecating their own Java runtime and that the major differentiation of said runtime from others is the much better approximation of the Mac UI in Java apps, and given that this deprecation is coming ~9 months ahead of OS X 10.7 Lion, I’m going to guess they are finally freshening up the OS X look & feel and don’t want to spend time keeping their JVM in lockstep.
There's an opportunity here that Apple should encourage. I write in-house apps in java on the Mac for deployment for my Windows colleagues. They are not going to stop using Windows. Java has real good libraries for rdbms access.
I guess the options are java develop in a vm hosting Linux or hello -ugh- mono. But I hope someone gives us a good java that runs natively.