Lordaeron lost the 3rd War, or rather, the lands of Lordaeron were betrayed from within from the Cult of the Damned and eventually Prince Arthas. But Lordaeron is overrun by the Scourge and most of the human inhabitants have been killed. There are only small pockets in Northern Lordaeron (Tirisfal Glades, Western and Eastern Plaguelands, Ghostlands, and northern Silverpine) of humans in anti-undead organizations like the Scarlet Crusade and the Argent Dawn. The Forsaken have de facto control of the Tirisfal Glades and Silverpine Forest, and from the sound of it in Cataclysm, they will also gain nominal control of the Hillsbrad Foothills. In Silverpine pockets of Dalaran mages cling on in Amberpine, and the Alliance village of Pyrewood survives as cursed worgen.
The city of Hillsbrad and Southshore fight for survival amidst the forces of the Forsaken. (Nature wins over Southshore in pvp.) The Kingdom of Alterac has fallen since its betrayal in the 2nd War, though it still lives on through the Syndicate. The Hinterlands are held by the Wildhammer Dwarves and a small remnant of high elves, but it is mostly inhabited by the native Amani trolls, including the honorable Horde-aligned Revantusk Tribe on the coast. Then in the Arathi Highlands is the fallen Kingdom of Stromgarde, whose fortress capital is held by the Syndicate, ogres, and Stromgarde forces. Trolls also roam the highlands. But part of the Arathi Highlands are held by the orcs and forsaken of Hammerfall. Finally there is Gilneas, the last of the unconquered kingdoms of Lordaeron (apart from the absent Kul Tiras), which will soon be under siege from the Forsaken.
This is a thread for idle speculation about the future of Lordaeron in the timeline of the game, though it will no doubt degenerate into Horde vs. Alliance sort of debates, which is not the intention of the thread. What do you believe will be the shape and condition of the continent of Lordaeron in the future?
There can be little doubt that the Scourge will be eventually driven from the lands, but it is questionable as to how soon these lands will be inhabited again by humans. The Forsaken also pose an interesting conundrum, in that as undead, they are unnatural abominations much like the Scourge. But the Forsaken have sentience and strong claims to the lands of Lordaeron. Yet it seems clear that unless the Forsaken find their own lands apart from the Tirisfal Glades, that they too will likely be destroyed in the long term. Of course, Northrend may eventually be an option for the Forsaken.