I expect what I'd like and what Apple will do are probably two different things, but I'm fine with the loss of an optical drive.
If they keep the 13" Pro, or fold it into the 13" Air, discrete graphics would be a nice option - it's not so popular currently, but onboard gfx + an mxm optionally populated for the 13" Pro would be great.
Lost the 1990s resolutions. I had a Vaio 10 years ago with 1600x1200 resolution, the 13" needs to move up to at least 1440x900, the 15"s should be standard with 1680x1050 and optional 1920x1200 or 1080. IPS panels would be very nice.
Using that optical drive space is likely going to upset quite a few optibay users, but I'd love to see a pair of Sata/6Gb interfaces retained, possibly in the form of the Air/blade SSDs, one populated, and the other BTO or user add-on.
Add a second TBolt port, and *produce* things for it - I don't care if Apple does it or someone else. Turn it into a universal docking port. If they want to make things even thinner/Air like, then at least for lower models, they could add discrete graphics via a sleek docking station, along with additional USB2/3 ports, possibly a slot for a pluggable optical drive, etc.
Thermals - if they moved to blade SSDs and removed the optical drive, let's get thermals under control. Ivy bridge will help to an extent, but then it will depend on what CPU speeds they select as well. SNB is damned fast vs C2D, let's keep the performance (of course, with some 10%+ speed gains) but work on the thermals/fan speeds/temps. Let's not go down the path of worrying if our machines running up to 100*C will de-solder our GPUs in a matter of years < 5.
USB3 - as stated, it's 'for free' with Ivy Bridge. I could live with a single USB3 port + single USB2 port (and TB). It would be great to see expresscard come back across the lineup, but unlikely, and if TB devices were available, not necessary. I hate to say it as a I do love my firewire, but same applies here. Give us a second wired TB port, and one becomes docking station + display, the second effectively expansion for whatever else we want, assuming adapters and/or devices are available.
What would be supremely stupid but not too surprising, is if Apple does *not* include USB3 on their Ivy Bridge systems - they had damned well be offering TB adapters or a docking station if they do this.
Give the Airs a single additional SO-DIMM slot and make their base RAM 4GB.
On the CPUs, I really don't care. If they keep the 13" Pro, move it to the lowest end quad core in the then current CPU lineup, with the Airs at dual core top-end, or move the Airs top end to lowest end quad, the 13" a step up and discrete graphics.
What I expect to see is the opposite - several Air looking systems with less expansion than today, as Apple tries to sell people on low local storage (put it in the cloud), and tries to commoditize laptops to the point that more people are willing to 'upgrade' every 1-2 years like they've managed on iPhones, vs those that may keep their laptops 3-5 years.
Sadly, while the media/graphics market is what kept Apple breathing for a long time, which included a good number of professionals, they've grown into 'mass consumer appeal,' and it's always a question of if Apple will ignore those professionals and their needs/desires in favor of more grandparents and teens buying whatever they can slap an Apple logo on to. I hope they manage to keep both, but it's definitely a concern, as not too many 'pro users' want thinner and 'less' at the penalty of performance and non-expandability.
