we don't know if there will be a f200 mk2 or what it will be.
For now, your choices are "wait for something new" "buy a F100 MK2" or "buy a F200"
F100 is well tested, has a lot of documented hacks and mods. But it has no touchscreen... that's the major difference. There is the Dpad, but you can modify your F100 to have a dpad if you are good at this kind of stuff.
F200 is brand spanking new, not a lot of people have it.... not a lot of DEVELOPERS have it either... so unless you want to act as some kind of "beta tester" you might want to stay away for it...
don't get me wrong, a lot of stuff works on the F200... but not everything is up to date, tested and documented yet.
Hope that helps...
If you name your needs and expectations towards the '2x, maybe we can give you better advice.
EDIT: Other choices are "wait for the craiginator" and "wait for open2x development" =)