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I know that this is an Air thread, but I thought I would give you a comparison to a 2010 15" MacBook Pro with an i5 2.4Ghz, and a Crucial M4 128GB SSD.

My boot time from sound to login is 18.6 seconds.
 
Sound to login screen is 8 seconds

Login to desktop screen is another 10 seconds

I am running Filevault2
 
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