It's not beyond the bounds of possibility for a future incarnation of the Raspberry Pi to be based on Intel's x86 architecture. The new RPi and Windows 10 announcement is more than just "another option". It comes along with official talk of the RPi now being a "real pc", opposite of the old argument used to defend RPi against more powerful clones. That mantra went along the lines of: We are not in that race - RPi is an educational device - processing power is not what the RPi is about.
Now that one goal of the RPi is it being a cheap personal computer, it sets itself inside the rat-race of specification wars. Performance becomes a more important vector in terms of design, and all avenues of hardware choice bow to it. At the same time, Intel is pushing itself down the road of mobile computing, in an effort to catch up with ARM, and all kinds of deals may be on the table. Intel have been steadily increasing their selection of development boards, and would surely love to cash in on the RPi hype.
Secondly, Windows on ARM is not really Windows as one knows it. As poor as Windows 8 was in terms of desktop adoption, Windows 8 on ARM (RT) was an absolute failure. The suspected Windows 10 on RPi will be the IoT version; a command line driven OS, akin to DOS. Just wait until the "zomg, Windows on Pi!" crowd realise. The yearning for mobile x86 will continue to grow.
We might be less suspicious of Windows appearing on the RPi if it weren't accompanied by mention of "six months of negotiations". This makes it less of a haphazard novelty, and more of a potential "partnership". Windows is always a source of infection whenever it appears on the scene, no matter how benign or marginal it may appear at first.
This is a "new" Microsoft however. A Microsoft that wants to be more laid back, "cool", and less dogmatic. A Microsoft willing to take a hit on profit if it means gaining community. It's hard to shake memories of what Microsoft-partnership did for Nokia however. A leopard never changes it's spots; a snake only sheds it's outer skin, etc.
We must remain optimistic though, afterall, the RPi never claimed to be a fully open-source board, and has always had secrets locked-up inside the Broadcom chips. RPi has proven to be so successful and spawned so many clones, that a worthy successor will quickly emerge, should anything drastic happen.
context: http://www.raspberrypi.org/raspberry-pi-2-on-sale/
