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any announcement is unlikely to happen before the wwdc. its about a week away so i dont expect much of anything until then.
 
iMac might not get Haswell until fall - most likely WWDC will be IOS 7/OSx next version and updates to MBP and MBA.

Haswell helps laptops more than desktops IIRC.

Silent updates like they have done in the past. They don't need to announce spec bumps on stage.
 
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