Assorted notes from Day One:
+After opening cutscenes and such, the game does a very good job of making sure you learn all the basics in a controlled environment (an isolated island with limited opposition and wildlife) before throwing you to the wolves, so to speak. It never felt like it was pulling its punches, per se, but it made sure you experienced different things first and had a chance to learn them (exploration, demolition, stealth, etc.) in a 'here's how' way that didn't feel condescending or useless.
+Aircraft are actually really fun this time. The rattletrap helicopters in Kyrat were useless usually- you couldn't go above an embarrassingly-low altitude, and they were tricky to control. The chopper I flew tonight was smooth to operate, didn't have any altitude restriction (or if it did, I never ran into it flying around mountaintops)... the floatplane was fun as well, with a surprisingly short takeoff distance and sharp controls.
+I do need to share that one of the early-available perks is 'Parachute', and I strongly suggest, based on experience, that you take that BEFORE flying anything. I was used to the old wingsuit from Kyrat... not wearing that here. Splat. ;)
+Proximity mines are awesome as always.
+Fire spreads MUCH faster this time- on more than one occasion we got singed from fleeing a fire that in Kyrat we'd have simply wandered away from- it outpaces you if you're moving at normal jogging speed sometimes.
+Wildlife feels a little less out of control so far than in the past two games- then again, it's still early. So far encounters include bears, cougars, cows, deer, dogs, and...
+Last note is on the other big one- wild turkeys. Vicious little shits- surprisingly powerful, durable, fast, they remind me of a feathered Kyrat honey badger. So GhostBear, using a flamethrower, is dealing with some cultists, and a turkey jumps in to attack them as well- and takes napalm for its trouble. No sweat- the turkey, while brilliantly-ablaze, ran across a road (leaving a trail of fire behind it) to attack another cultist anyway. Because of COURSE it did.
This one? This is really great. (And making me nostalgic for my Rocky Mountain homeland)