It will be the same as every year.

An orgy of new stuff, only 10% of which will actually be available on the market by the time of the next (2012) show.
A resultant flood of posts on the interwebs from people crying that these wonder products are not yet available.
A complete failing on the part of these people to instead invest that money they have earmarked for the new wonder-thing on ammo, magazines, training, and practice.
More picture threads, picture posts, and "build" threads of pristine firearms that are rarely, if ever, you know... fired.

Many of these products will actually be good products, useful products, and will actually be put to use by a very small percentage of the gun-buying public. And thank God for the picture-posters and safe-stuffers as without them those that actually shoot would have to pay through the nose for one-offs and custom made parts. Ecconomies of scale, and the 100 widgets sold to the 1 widget used ratio are the only things that keep manufacturers producing.

Nothing shown at SHOT will drastically change the AR15 commercial market. Nothing. The only drastic change you'll ever see to the market is legislation outlawing them or the US military scrapping the M16/M4 and going with another platform entirely, and even then it will take years for any effect to be seen.

Instead we see small trends. Smooth FF tubes in place of full-rail systems. Smaller and lighter red dot sights. More, and wider ranging, low-power variables (I got an email on an interesting concept that has a red dot up to 3x and then changes reticules to something else after that, kind of neat), marginal changes to magazine construction and capacity, etc. Maybe some new, incrementally better, silencers, grips, etc.

and no amount of gear, widgets, or upgrades will get people out there actually shooting the guns.