+1, it also really depends on the offset (as to whether it's a scam or not)—like I talked about elsewhere, even our low-cost offset is a much more credible project than some of the credits frequently purchased by big companies.
If we don't start changing the standard for what's acceptable, who will, ya know?
Incidentally, do you have any advice or resources for assessing the credibility of carbon offsets (for purchase by individuals I suppose, not that it should make much difference)?