I don't know if your are worried about having a "refurb" Mac, but I myself waited to buy a new MacBook Pro and an iMac 24" just this past week. I have the budget to buy NEW, but from my own previous experience (and many others) a refurbished Mac can be a GOOD thing. Just about all of them will come to you looking new and untouched, but you will have the benefit that that particular computer need to be looked at specifically by someone inorder to pass inspection and not just leap off of the assembly line like most new things.
From experience, not does the willingness to wait 6 months or more often result in some pretty good price reductions, but as suggested, one could be confident in the inspection and any touch-up necessary for the unit to pass inspection. It's not an obviously advertised benefit, but given both the price reduction (any over 30% off is really good), and new parts (unlike some company's "refurbs") may actually be put in (display, drive, memory, etc. - whatever caused it to become refurbished).
It may be just me, but I generally find the APP worth the price, and make sure to active /register it.
PS I just had a drive replaced, and the "Serial Number" as show in the "About This Mac" box no longer looks like "W8504..." or "RFB..." (which I've never seen" but "Serial Number SystemSeumb". I was told once when the MLB (main logic board) was replaced there was no way to put the original Mac hardware serial number back on, so it had no serial number (i.e. blank). But the above looks abbreviated, and not at all useful for software that ties itself to any aspect of a hardware ID (e.g. Retrospect, copy-protection, TechTool Deluxe, etc.).
Anybody have a one-stop solution for this, or is it like I suspect, a case-by-case basis?
I'll update here if and as any solutions find their way to me. Happy hunting.