Conversation in the Apple-focused blogosphere is all over the map this week, but with Apple in the tech world’s driver seat these days, wide-ranging activity is only to be expected. Out of dozens of news nuggets, here are three that create some interesting glimmers: iSuppli’s teardown of Apple’s diminutive iPod shuffle reveals a tidy profit margin; AT&T reportedly wants to keep its lock on the U.S. iPhone channel; and Apple is offering an $899 iMac — but only to educational institutions.