Just as a follow up, I'll kinda give a brief summary.
Though it resembles Counter-Strike and Tactical Ops, Frag.Ops plans to take the counter-terrorism gameplay into a new field of play. Frag.Ops strays from Counter-Strike a bit, in that it has faster gameplay, and a bit less realism (mainly to change from the slower pace of Counter-Strike).
Frag.Ops consists of the two teams, the Special Ops and the Mercenaries. Now that public terrorism has ended, only privately contracted mercenaries remain, commiting such acts as smuggling.
Frag.Ops has a variety of weapons, which will eventually be mostly different for each side. However, due to the early stage of this mod (the mod is still technically in "alpha" stages), the two sides currently share some of the weapons. Many may recognize one of the newly implemented weapons, the traditional M4
Frag.Ops implements the usual cash and round-time gameplay, and the spectating of others when killed. It has a variety of skins and gorgeous graphics, yet the frames in the game are still great.
That's where the similarities end however. Frag.Ops accelerates past previous games, by supporting vehicular assault, such as this one:
Frag.Ops v 1.36 will only feature this vehicle, but many others are in development.
Frag.Ops also has the AP (Action Point) system. This is basically a simplified stamina system, that doesn't slow down gameplay, but rather it accelerates it. Currently, the AP's can only be used to sprint for a few seconds, but eventually climbing, dodging, and other such maneuvers can be attained with these AP's.
It also has a medal system, to award marksmanship, skill, and overall ownage.
When Frag.Ops moves to version 1.4, it will officially move into the "beta" phase, and will feature more vehicles, including an air arsenal. A new gameplay style, tentatively titled "War mode," will host these new slaughter machines in vast stages. The gamestyle will use a wave-spawn type of playing, similiar to that of UT2k4's Assault and Red Orchestra's reinforcements spawning.
Frag.Ops 1.4's War mode also plans to implement a "build" feature. You will be able to use your money to construct buildings and other such contraptions to help you attain victory. One such example includes a sniper tower.
Well, that's my FO description, it's a bit long, but I hope it will answer some questions
Peace out