iMac - highly possible they will drop the optical drive, then make the whole thing thinner! Maybe they will have an ultra-thin version with only the Intel HD 4000 graphics, and hopefully keep a thicker version with discrete graphics.
MacBook Air - I assume this is referring to a 15" and 17" MacBook Air, and the discontinuation of the MacBook Pro. Don't worry apple will keep at least one notebook with a dedicated graphics card, however their focus will be on ultra-thin notebooks with Intel HD 4000. Unless if somehow Apple finds away to innovate and put a high-end discrete graphics card in the MacBook Air form factor.
For the imac I don't care if they drop the optical drive, but I hope they don't go thinner. It makes zero difference on available desk space shaving off a couple millimeters on such a machine, and those things have too many heat issues as it is. If by some chance they do drop the mac pros, I hope the imacs become a bit more serviceable. As it is they have too many parts where servicing requires taking the computer in to Apple. It's a lot of potential downtime, which can be an issue. Display, hard drive on 2011 machine due to the temperature sensor thing, graphics card isn't just a pullout type like on a mac pro, etc. Even on the mini most parts are more accessible.
For the macbook pros (if you think we'll see a 17" air you're insane, they'd just drop the relatively unpopular form factor) smaller is going to mean tighter component integration. Apple doesn't actually use high end graphics in any of their laptops for battery life reasons, and innovating does not mean attempting to stuff bulky high wattage parts into a tiny enclosure. The best direction for this line would be focusing on some real improvements for the integrated graphics associated with the Airs and writing the best drivers possible.
MacBook Pro sans optical drive as thin and light as Air? YES! i7 quad, SSD, 2gb VRAM, 16gb RAM? YES! 'need a fast machine to grow with FCPX developments.
I'm not sure if you're serious at all here, but none of this is really possible in that form factor yet or with Ivy Bridge. The earliest you might even start to see powerful processors in something that looks like a macbook air is 2013. If you're doing heavy video work why would you even need such a compact machine? Power should be the primary concern. Just using a laptop at all there is a pretty hefty compromise. If you require a lot of supporting hardware, you're going to be pretty stationary anyway.
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Getting worried and thinking my next Mac may not be a Mac at all. Love my Macs, had them for 10 years but once my current 2008 unibody mbp bites the dust, i just can't afford to replace it with a NZ$3000 one again, especially when the specs are not that great anymore. I'd love a new MBP, but apart from Windows my wife new $1500 Sony trounces it. Sigh.
I'm still not sure why Apple is so expensive in NZ and AU. It's absolutely stupid what they cost in those countries. I know in AU electronics in general are pretty overpriced though relative to what many other countries pay.
Dang it, I bought the 2011 MacBook Pro in March, and the iPhone 4S a few weeks ago. Technology advances so rapidly nowadays!
What is surprising here? It sounds like it advances quickly, but it's not very linear. Some years you see very little gain. Intel doesn't have anything really interesting until 2012 anyway, and if Apple really makes any major changes to their enclosure, do you really want to beta test the design for them? Regardless of hype, the next ideal time to buy would be 2013 or later, as that marks the next big jump for intel. If they try to cram the macbook pro as it is into a smaller enclosure, you don't want to know how hot that will run.