This is what is going to happen across the Intel CPU space:
http://www.tomshardware.com/news/upgrade-card-Core-i3-sandy-bridge-Best-Buy-scratch-off,13225.html
MB makers won't need to stock the same MB with 25 (or even 10) different CPUs soldered onto them as an equally-high number of SKUs. They'll ship each MB with perhaps 3 variations (i3, i5, i7) and allow end-users to upgrade with these Intel CPU upgrade cards or something like them. I expect that the mainstream socket (e.g. 1155) will be only BGA, and to get a LGA socket you'll need to buy the extreme platform (e.g. 2011), at the corresponding astronomical price. If even
that is an option anymore.
Given that the vast majority of all new computer hardware is either a tablet, a laptop, or a workplace desktop, I understand why this is happening. I don't
like it, but I don't foresee anything happening that could prevent it. What is the additional COGS to Intel if they sell a 3570K configured as a 3330? The
price difference is currently $30 (newegg). But if the buyers who wanted a 3570K to begin with can get one by buying an upgrade card for $50 (or more likely, $150... ugh), then who's to say that any
mainstream consumers are worse off? Keep in mind that OEMs will be able to reduce costs by not having to put a CPU LGA latch mount on each MB, not having to deal with RMAs from bent pins etc., and not having to test, certify, and support a MB with each of 25 different CPUs that happen to fit in its socket. Also, they'll probably get a small cut of each upgrade option, since they will need to have tested it. The available upgrades for a given MB will be locked. The set of CPU / MB configurations will be locked. Upgrades will be expensive, and will be ROI/benefit-priced rather than cost-priced. Enthusiasts lose, Intel, OEMs and L-C-D consumers win. OEMs will make up marginally-higher prices on base CPUs by benefitting from lower MB costs and future upgrade profits.
Of course, upgrades will be constrained to whatever was the best feature set for the CPU model you got when you bought - which you may not even be able to determine in advance. And they will cost a pretty penny.
Only two things combined will change this:
1) AMD or ARM needs to be able to compete with Intel's best CPU performance, AND
2) Mainstream must-have software must have desirable and easily-discernible behavior benefits from faster CPUs. Whether that software is facial recognition, speech translation or whatever, it needs to require lots of CPU power, not be runnable on a GPGPU, and be something that no one can afford to do without.