Apple and the Pro Market (Professional and Prosumer in my case).
Keep in mind that many of the Pro hardware and software, when they are released are quite near cutting edge, the software is vastly complex. When we hear Steve talking about, we've been working on this (iPhone 4) for 18 months, how long do you think they work on other products.
There are obviously different prototypes, designs, as well as prototypes from other industry partners, be it intel, samsung, etc. Apple isn't just gonna release something when we want them too (although it'd be nice to see steady upgrades from time to time...).
We all should keep in mind that the Pro Market often leads the core Mac in terms of technology, mostly because they have the room, often times the tech finds its way into the consumer products but overall they often start here.
Expandability is another 'Pro' must, how many video professionals have a PCI-x/e/express that has a video decoder, breakout cables etc. There is no honest USB solution that will make the iMac Pro.
So in the meantime, and i know I'm one that has lead the pack, lets use our best judgement to buy or wait, and it's great to get feedback from other mac users. At the end of the day, we all don't know anything, and are all looking forward to 'next tuesday.'