I think their brand of CS seems very trivial and stupid, but in reality, it's very smart. For example, as hazed pointed out, c9 took arch control on Inferno, and smoked the wrap. They left wrap, and SK retook it, thinking it would be a B hit. then c9 walked up wrap to A site and won the round that way.
The 3-pushing through CT smoke was an extremely smart call. They knew FALLEN was awping there. They knew, at best, he could get 1 player, then would die. They executed it quickly enough that nobody could be rotated in to CT fast enough to save FALLEN.
Maybe it's because I'm a Cloud9 fan, but everything they do seems to be structured or have some underlying plan behind it, which is nice to see after the shitty puggy style they've used for years.