C&C: Generals was excellent. I only played two games for years in row after they came out. The first was Generals. The other was Company of Heroes. Well-made RTS games just have a longevity that no other games have for me, not even MMORPG's.
Normally I don't play "normal" RTS games anymore after playing CoH; C&C3 SP was just "ok", didn't even bother with RA3 and I'm not all that excited about Starcraft 2. DoW2 is really good, but perhaps a bit too simplistic and intense - i probably liked the CoH balance the best. But I actually think that the Generals series could be the exception, that there's a place for a Generals 2 with just little (but still some) innovation from the first. Keeping an eye on this title for sure!