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I ordered my iMac now deliberately so that I could get it with Mountain Lion. A new OS is always going to be buggy, and I'd rather have a fairly stable OS to begin with, and then I'll upgrade to Mavericks once it's been around for awhile.

Hmm... this is a good point. New OS can be buggy. However, I have Mountain Lion in my App Store account so I could theoretically downgrade if I really needed to.
 
My wife decided to get a new 2013 iMac and we'll be waiting for Mavericks. Waiting for less than a month isn't a big deal for us.
 
I'm in the market for a new iMac to replace my 2008 that keeps freezing every day or two. No idea WTF is wrong, but I suspect hardware.

Anyway, I'm waiting until Mavericks is released. One less thing I need to mess with on the new machine.
 
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