id Software's Quake was a game which started the age of user modifications such as Threewave Capture the Flag (capture the flag! grappling hooks!) and Team Fortress (yes, that Team Fortress). Threewave's level design popularized a very symmetric map design that forced a red and a blue team to compete using speed, power, and intricate knowledge of the maps that matches took place on. Team Fortress popularized the idea of having gamers choose from any number of "classes," all of which had their own benefits and drawbacks, to play a violent capture the flag match across maps designed using the concept of player bases being connected to each other by a very deadly choke point where a good majority of the player-to-player battles took place on. The strangest aspect about both of these mods is not how their game types differed in some basic mechanics but, rather, how each was designed around the same mechanics: capturing another team's flag in a level designed around a series of choke points (the flag room in each base and the middle of the map where the red and blue bases were connected).
Counter-Strike and Counter-Strike: Source serve as the best examples of a level design methodology which focuses on choke points and capture points (bomb sites) as a means of enforcing teamwork (three popular map layouts are below). When playing maps where planting and detonating a bomb are the focus there are is always the choice of one of two bomb sites where a bomb can be planted. There are, generally, two or three entry points for each bomb site and each of these entry points are typically narrow hallways or areas of very low visibility for those attempting to storm a bomb site. In order to succeed in a match, the terrorists have to be able to split up their team into a decoy squad and a bomb planting squad and convince the opposing team of counter-terrorists to take the decoy bait while the bomb planting squad can plant a bomb and setup their forces to defend all bomb site entry points. The other alternative, of course, is to have an entire team rush a single bomb site and hope to confuse the opposing team and kill them all but most maps in Counter-Strike are designed to give the bomb site defenders a tactical advantage in both visibility and cover. When terrorists invade a bomb site they are generally required to all pass through one hallway into a wide open map segment or antechamber which, by the nature of being less confined, gives the advantage to the defenders.
Where Counter-Strike influenced tactics using a series of confined rooms and hallways, the Battlefield series presented strategic and tactical options to its players on a vastly more open scale. Battlefield 1942, Battlefield: Vietnam, and Battlefield 2 all presented players with a very large toolkit of weaponry, vehicles, and air support as a means of dealing with the intricacies of a map that presented the indoor confines of miscellaneous structures, small towns, and, most often, the great outdoors with only terrain to shield a roving infantryman. The level designers at DICE, developers of the Battlefield series, created the maps of their games under the assumption that littering the landscape with a handful of capture point would be enough to create venues for battle amongst its online player base as each of the two opposing teams on a given map fight for dominance of every single one of a map's capture points. With Battlefield, DICE took the wide-open gameplay of games like Tribes and, basically, changed the "capture the flag" gameplay style to be more of a "capture and hold a bunch of flags" that moved a team ticket counter in a tug-of-war fashion that, after a certain amount of time, awarded victory to the team who was frequently able to hold the most points. At the time of its release, the wide-open planes-against-tanks-against-jeeps-against-infantry gameplay of Battlefield was revolutionary and created these huge team-versus-team conflicts that lay vivid and powerful in the memories of the players lucky enough to play in a full server of friends.
It is from games like Counter-Strike and Battlefield, along with historical battles like that of Thermopylae, that we see more games being released over the last couple of years that put an increased focus on points and the tactical situation in which they are placed in. All of Company of Heroes' maps, like the one below, are designed around a number of resource points that are used to collect resources passively while the game occurs. The stars on the map are capture points that are the primary item of importance in a game; similar to the capture points in Battlefield, these points in Company of Heroes determine the rate at which a team's ticket counter ticks down to zero -- the first team to hit zero loses. Almost any battle in Company of Heroes revolves around these points and their location on the map reflects their importance; they are typically placed on or near very tactical locations on a map such as a bridge in the middle or on an island-like landmass that can only be accessed through bridges.
DICE's latest game is the undoubted culmination of a point-based game design where a map's choke points double as its points of interest. Battlefield 1942/Vietnam/2 proved that players flock to the entire area surrounding a point of interest but if a map have six or seven capture points and sixty-four players (thirty-two per team) each point ends up attracting a fraction of a total player-base for a map and that, as a game design, ends up becoming a flaw in the overall experience. The progressive capture point format of Battlefield: Bad Company, where only two active points of interest are accessible by the entire player-base at a given time (and they're relatively close to each other) allows a match to be a consistently focused experience where both teams are honing in on a set pair of objectives. Instead of thirty-forty players being required for a good game like in the old days of Battlefield 1942 and Battlefield: Vietnam, Bad Company provides a high level of intense combat even if games are limited to seven-eight players per team (maximum is twelve-versus-twelve). It's worth noting that Bad Company executes this design while maintaining the relatively large map sizes that are a "trademark" of the Battlefield franchise; which goes to show that it's possible to provide a very focused gameplay flow amidst a large game map with a well thought-out design.