Apple's UK Store leaks some information which suggests that 8-Core Mac Pros are coming soon.
When searching for "Mac" in the UK Apple Store, the listing for the Mac Pro is:
Mac Pro
Now quad-core or 8-core processing power.
Configure yours today.Rumors that Apple would incorporate two of Intel's Quad-core chips into a Mac Pro to produce an 8-core Mac Pro have been ongoing since late last year.
Latest Update: Apple appears to have found it and have removed the text from their site.
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