The gambit part is a lot similar to FFXII's, though the whole thing is accessible from the get go (i.e. no need to buy gambits :P). You have some preset behaviours which are dependent on your character's class as well as room for custom sets too. FYI, the gambit system is called "Tactics".

That aside, the combat system is somewhat RTS. You can manually select any of your four party members, by doing so you override their Tactics. You can also pause anytime and go from each character to give them their next move (where it is moving, changing targets, using specific skill, etc...). You can also do this in real time too, just depends how fast you are at switching and such. Also, each characters can have two weapons set up. Like my Rogue dual wields (long sword and dagger) and his secondary is bow and arrows, another example is Alistar (is a PC you find early in the game, not spoiler since you find can go to the official site and it has had all the PC characters' names for a while now) who I have with Sword & Shield on primary and Two-Handed on Secondary. Switching between them is smooth and easy.