All responses you get to this may well be dependent upon where you plan on going to hunt. All Merriam's turkey habitat, population densities, conditions, etc. are not the same. You may hunt high turkey density, river-bottom areas,...or you may hunt high-elevation, low turkey density areas,...or anything in between.
Your classic, high-elevation, mountain Merriam's turkey hunting,...if that is your choice,...would likely require being in somewhat "good" condition,...and prepared for all kinds of weather conditions from 90 degree temps to hunting in snow. You should also be prepared to be very mobile, and with a mentality that you have to cover country to find birds to hunt in a lot of cases.
Merriam's turkeys are generally quite vocal, even in the fall. Gobblers will often gobble on the roost, just like in the spring, and hen/brood flocks will very often be talkative, especially at first and last light.
Personally, where I live, I have quit hunting fall turkeys just because a) there is not the same "thrill" for me as in the spring,...and b) quite honestly, fall turkeys here are just too easy to kill,...or at least they used to be when I hunted the fall.
A summary of my advice would be: come prepared for all sorts of weather and conditions; plan on covering lots of country to find birds to hunt (don't assume turkeys are spread uniformly throughout the area you are hunting,...they most likely are not); then hunt the ones you find using fall calling tactics (not all that much different from in the spring).
