And really, has there been a better Computer RTS game that comes close to it since?
I'd argue for Dawn of War, Rome total war (for all it's flaws) to name two. Warcraft 3 was a painfully slow game in skirmish games, it took ages to afford units. Dawn of war is much faster, much more exciting. Not only that, but the units were both better animated and were simply better conceived.
To go on a huge tangent, Company of Heroes, the new game from the relic guys, is fantastic. It's like Dawn of War, but realistic
feeling WW2 combat, with heavy emphasis on fortifying buildings, with a more mature version of the Dawn of War resource type (instead of a generic requisition and base-built energy, you get Manpower, Fuel and Ammunition capture points. Fuel is used for tanks, Ammunition is used to activate special abilities like the Calliope Barrage and use high-level doctrine powers like Call Tiger Ace, and manpower is used for everything in general. Basically the best part about it is that they managed to make a game that feels like it's a real WW2 battle, but fun fast and exciting. As opposed to the days of Close Combat, 4 hours to move your guys across the street.