At the risk of having a Captain Obvious moment here, I think it's safe to say that the "we want Merom" posts are getting a tad old at best. That horse has been beaten far beyond anything resembling a humane death.
The fact is that while there are a select few of us (don't kid yourselves, the people who post on this forum represent a tiny fraction of Apple's customer base, albeit a loud fraction) that know the difference between Core Duo and Core 2 Duo, the VAST majority of users and customers neither know nor care. And to be perfectly honest, the speed difference in 99% of the things people use their computers for are unnoticeable. Try it for yourself. Web pages load at the same speed, email is sent at the same speed, and IM's come and go with the same frequency.
The truth is, Apple doesn't really care all that much about who is or isn't shipping C2D. They know that once they come out with the next big thing, all us Photoshop users and media producers will skamper to the website and order ours just as we would have if it came out a month ago. They have stock of MB and MBP to clear out, and there's no reason for them to rush into selling a processor that most people don't even know much about when their sales are still high. Their business is great, and more importantly, their big push right now is obviously iPods for the holiday season. This is a much more popular gift item, and the holiday shopping season is barely gearing up.
C2D (or whatever is next) will come when Apple sees novelty sales for the iPod starting to die down. Not before.