I am about to get civilization 5 but there are some things that bother me. The game is on steam and is cross platform on steam, does it also hold if I buy a PC version of the game in store? Amazon has the Windows version for 23 pounds, whereas mac version is 30, 7 pounds is a pretty good saving if you ask me, so I figured I'd buy the windows version, activate the key on my mac and download the mac client. Could anyone with retail Civ 5 check for me quickly if the game shows up as both windows and mac in their steam account?
I agree with your logic and it would make sense, but don't know the answer on this one. If you can hold off on it for a while, it may appear in either the current thanksgiving sale or the christmas sale, saving you some cash. You could try asking steam support if a PC CDkey is valid for steamplay in this case.
civ 5 uses steamworks so that means whether you buy it retail or not, it will require steam. it's also mac compatible so you can install and play it on both OS's without having to buy 2 copies.