I think it's simply because they have to provide the OS version now. Previously, Sun did that for them. They may be 'pouting' that they have to do it themselves? Of course, if you try to run an app that uses Java, it will ask if you want to download it and then proceed to do that, if you reply "Yes, of course, why didn't you just include it in the first place?
!" Perhaps they began to realize how long the original download was going to take? Of course, they'd rather have developers just make OS X native apps, anyway, especially now that the kernel is 64bit! I'm not sure previous (or the newest) Java versions would/could take advantage of that.
The above, of course, is pure speculation on my part. But I once played an Admin in a forum...