Total Annihilation Revival
Sure, when you zoom right down your not going to be looking at Company of Heroes style graphics, but then when your playing games that have up to 3000+ units in a game, who cares =).
Unlike most games, Supreme Commander wasn't made to focus on a single battle, but more on an entire war, and the sheer sense of scale this game brings to the RTS genre is a constant reminder that this isn't just about one little fight.
For anyone who wants to say "oh winning is all about the bigger and better stuff, same as any RTS" then you haven't played this game enough ;). TA was still somewhat along those lines, but Supreme Commander does away with that entirely. Sure, those experimental guys can really hurt, or if you've been to slow to get up the right defences, a nuke missile is going to cause you a world of pain. But while that player is building his experimental, you can pump out enough smaller guys to match it in the field, and then some. And if you were keeping an eye on that guy with the nuke like you should of been, you would of had the nuke defence systems up in time.
Players who like to turtle and build up big can do so, if they know what they're doing. Players who like to rush with hordes of smaller units can do so on a scale like they've never been able to before (400 little tanks/bombers is always going to cause some pain). Players who like to be sneaky... here's a little tip... use Cybrans, with mobile radar stealth vehicles and air transports ;).
Naval combat has never looked so good in an RTS. Dogfights with 200+ fighters... need I say more? And ground battles where your units range from tiny little bots (bigger then trees) to massive walkers and mechs that make those bots look like ants. Oh and combining all 3... sometimes you forget all about your battles plans and just sit back to watch the absolute magnificence of such a battle. Supreme Commander has brought back the term 'instant classic' to the RTS genre, and it's one of the few games I can truly say I'll be playing for years to come.