In my opinion, this game is definitly a Game of the Year back in 2002 or 2003. This game is like the good old Starcraft; simple, quirky and FUN!!! This game is very easy to learn and not complicated unlike Blitzkrieg, Medieval, or Rise of Nations and it can be mastered within a month if you are already familiar with the Blizzard games.
Requirements, like Blitzkrieg, is no problem. You can enjoy a single player with a Celeron 900mhz, 256mb ram, GeForce 2 MX400 (I have tried it on this PC) while the multiplayer needs a better rig such as Athlon XP 2000+, 512mb ram, GeForce 4 MX440, and at least a Cable or DSL (I have also tried on this PC) to play without any lags or any slowdowns. But speaking of lags, lags IS a big problem on Battle.net. Even though you have a good rig and a broadband, the opponent or an ally of yours might have the worst PC that you can ever think of but this is not very common.
Multiplayer, is simply the best feature in this game. You can play many mods (you already know what those are) and play the multiplayer game itself. But more people plays mods and it's a good thing. Like myself, I like the original RTS multiplayer games but some might like mods better which gives more choices for people and raises the replay value.
Finally, one word, a must have. Sorry, I meant three. Having to include a Game of the Year and its expansion, this Battle Chest is a must own. This game is one of the best that you can ever wish for but if you do not agree with me then you probably have never played the game before. (To make it simple, just think of it as Starcraft with more maps, different units, and better graphics)
P.S. But if you did played the game before and you don't agree wth me, you are out of your MIND!!!!!