i think your over-reacting to extremely limited info. first off, regarding religions it doesn;t say they are gone completely, it says they will different than in civ4 without explaining how.
as far as one unit per hex, im looking forward to that. you can't think of it like civ4 with only one unit per tile, its a new game with new mechanics ect. i think it will lead to alot more involved strategies. lets be honest, in civ 3 and 4 the extent of military strategy has been:
step 1: produce as many units as possible.
step 2: stack all units on one tile, then move that stack to your opponents city.
step 3: if your stack is bigger than his, congratulations! you win a new city! if his is bigger, return to step 1 and repeat till successful.
by making fewer units and forcing them out of cities and into the countryside, they have created an enviroment where you have to think strategically. if you do not, enemies will be able to out maneuver you, flank your artillery and deny your frontlines the support they need to hold. at which point a hole is opened up and the enemy can push through, but they are just as limited as you are, so you can bring in reinforcements and cut off their thrust, surround them and destroy them. all of this taking place miles from a city in some otherwise unimportant desert that only matters for its strategic value and would have been utterly ignored in the civ4 system.
stroke and counter-stroke. the new system will make things like forts actually useful, and imho will make this military aspect of the game infinitely more interesting.
some people commented on the difficulty of arranging units with one unit per tile? i would imagine that that has alot to do with giving units 2 movement tiles per turn, as friendly units will likely be able to pass through each other so long as they don't stop.
regarding mods, i can almost guarantee it will be just as moddable as civ 3 or 4. games don't have that level of moddability by accident, i cant imagine why they would decide to stop doing it now. Mods have kept civ 4 alive and selling copies YEARS after other games released at the same time were long forgotten.