Darrell Etherington for TechCrunch:
Before today, you needed a developer account to help test Apple’s upcoming software releases before they hit the general user population. You didn’t need to actually develop anything, but it would still cost you $99 per year to partake, and technically it was still sort of against the rules. Today, Apple introduced its OS X Beta Seed Program to make pre-release Mac operating system software available to all who want to help try it out.
My wild-ass guess: OS X 10.10 (11?) is a radical change and Apple can’t wait to show it off, but they’re not going to be ready to ship a stable version this summer or this fall.