When I first played Tactics, I was expecting a game mixing Fallout's gameplay with a strong focus on tactical combat. Well, there is alot of tactical combat allright, but the gameplay outside of combat disappointed me.
Fallout Tactics plays largely like a straight squad-based tactical game like Jagged Alliance with only superficial similarities to Fallout. As far as RPG elements go, your characters level up, you can raise their skills, etc. You can walk around outside combat and talk to NPCs, but there isn't any real meat there and these parts of the game feel tacked on and pointless.
The game improves on Fallout's combat system, but as straight combat game it still feels lacking, especially in turnbased mode. UFO: Enemy Unknown or Jagged Alliance are far better games in that respect, and I can't recommend Tactics for it's RPG elements or because it adds anything to the Fallout universe either.
Ultimately, I found Fallout Tactics to be simply forgettable. I wish I could see what others appreciate about it. To me it felt like the ultimate bad compromise: Neither a good staregy game nor a good RPG or even a good Fallout game.