If I had to bet money on WWDC announcements, I'd probably go with Gruber's predictions. Nothing mentioned stands out as particularly unlikely.

And that's why these predictions worry me. If you do the mental equivalent of zooming out, these predictions seem to focus on two things:

1. Centralizing storage of user-generated content.

2. Catering to consumers instead of professionals.

The vast majority of Apple's value captured (AKA revenue) is from consumer products: iPads, iPhones, iPods. But much of the value created by Apple products comes from professionals. Artists, programmers, writers; countless creative professionals use Apple hardware and software in their work. If Apple focuses on consumers, it will almost certainly be to the detriment of professionals.

I love my MacBook Air, but I can see Apple's trajectory. I can see my laptop becoming a locked-down Duplo version of itself. Then I'll be forced to switch to something else, and my knowledge and experience of OS X will become worthless. More importantly, many other professionals would be in the same boat. Millions could be stymied and frustrated by these changes.