A well-designed and polished game
My favorite RTS series of all time is Red Alert, so I decided to use that game as the standard against which I compare this review. Overall, CoH is an original game with good gameplay and great graphics. The one criticism which sets it back, is that I didn't find it very enjoyable or addicting like I find most RTS games. There were a lot of annoying tasks I had to do that I didn't really find appropriate for an RTS game, micromanagement of the units was the foremost of them.
I'd like it more if I could just tell an infantry to attack, instead I have to deal with grenading clumps of opposing forces, or satchel charging a fortified building. In this respect the experience has primarily been one of a third-person shooter rather than a real-time strategy game. Another example is how one needs to turn a tank to avoid fire to the rear (low-armored side) and then take advantage of this circumstance on opposing armored vehicles.
The resource accumulation mechanic was new, but I think I prefer the usual system of harvesting resources as opposed to needing to control vast amounts of land. It's less realistic, but its not as fun and can get really frustrating when you are facing a good enemy in multiplayer or are on a higher difficulty setting.
Now, for the praise. I enjoy the cut scenes very much, as they include nice music and a detailed overview of the situation and the context with which your missions are performed. I especially like that the protagonist of this game is a ~20 year old kid. He's never experienced the intensity and horrors of war, and some cutscenes, like the one in which he wastes ammo gunning down enemies very violently, expose this fact to the player. Although very typical war movie emotion, I applaud its inclusion in the game. In many games, I can't really relate to the main character. I'm not a 7 foot, 300 pound hulking tough guy made of muscle (like Gears of War), and not only can I not relate to that person, it doesn't even seem realistic.
If I had to give it a score on a 100 point scale, I'd give it a low 80. I just don't see why everyone calls this game one of the best RTS games ever. The fun factor - the part that makes games addicting and enjoyable - is by far the biggest weakness of this game.
***EDIT****
When I wrote this review, I had only assessed the single player aspect of the game. It has since become apparent that the real highlight of this game is the multi-player, which is far more fun and enjoyable. I think Relic still has plenty of room for improvement in their campaign, but their multiplayer component is solid. For this, I have increased the score to 4. One of the criticisms I will maintain is the resource acquisition mechanic, which forces you to hold vast amounts of territory. This design can get really frustrating, and I think I would prefer the classic method of mining or gathering resources.