Military Strategy games have a hard time appealing to everyone. Make it too much of a sim, and it can become a crowded, buggy mess. Make it too simple, and you can lose immersion among the simplified UI and arcadey combat. Full Spectrum Warrior is more suited to the latter than the former, but manages to avoid some of the pitfalls of streamlined action-strategy games.
If you've played games like Brothers in Arms, you'll have a good idea of what FSW has to offer. In fact, the game cribs very heavily from Gearbox's WW2 FPS series. You're put in control of one or more teams of soldiers or armored vehicles, and must coordinate their fire and movement to out-maneuver enemies.
The mechanics are simple, and fun, and can be quite challenging in some areas. Unfortunately, you're not given too many options to move around, and flanking spots are made pretty obvious by the game design. Otherwise, everything's very streamlined, and you won't run into too many issues with glitches or AI.
FSW is a game with solid, easy-to-grasp concepts, and manages to throw enough surprises to keep the game feeling fresh from the beginning to end. there's not much to this game besides the feeling of achievement by overcoming its obstacles with minimal loss of life. It's a fun little campaign that you may play again to see if you can do better than you did on your last run. It's best appreciated as a thinky little action game that you finish off on a lazy weekend.