Is that they don't have their publications (research, policy studies, etc.) online.
Either they haven't really figured out that the web has significantly changed from 1999, or they think they will loose out on revenues. I understand partly, but really they are loosing out on a lot of impact by virtue of simply not sharing what the "tank" "thinks". If they did, media persons, students, foreign researchers, bloggers(yes, me!) would have been able to use some of their research much more easily.
As it is, I (and possibly many people) won't bother to buy any of their stuff. Not that it's necessarily too expensive, but who can be bothered?
I specifically level charges at Institute for Policy Studies(IPS), Point Pedro Institute, both of which seems to do decent work. Lirneasia seems to do a better job, but again, where is the research? happily, CPA is an exception.
My all-time favorite think-tank is Cato, now that's how it should be. Even my buddies at CCS gets somethings right on the web, but things could be better.