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Don't expect discounts from Apple itself. They didn't do anything last year.

So you're left with third-party retailers like Best Buy and B&H. Judging on past years, the recency of release is not a mitigating factor for discounts, provided there is available stock. Availability, in particular, is the big concern given that the the first MBPs will not be shipping to buyers for another week or two.
 
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