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1. John Gruber's Take on the Announcement
2. MacWorld's Article (Actually a bunch of articles)
3. Panic's article on Gatekeeper (Though I think calling the current OS X "like having a jailbroken iPhone" is a bit of a reach.)

FWIW, I like a lot of the changes in Mountain Lion.

P.S. Notes on OS X, eh? Good, but does that mean Stickies has gone the way of the dodo?