What do you mean "what happened to them"? First of all, PNAC is only one small branch of the Council on Foreign Relations, who are the ones who have always dictated American foreign policy since 1921. The people in PNAC are merely the chosen frontmen for this agenda in the Middle East. The same people who wrote Clinton in '98, urging him to invade Iraq and remove Saddam Hussein, are still working close with the administration today, and are now pushing for war with Iran and eventually Syria. The Project for the New American Century was writing a decade ago about the things we now see unfolding. They are the ones who, in early 2001, published "Rebuilding America's Defenses", which stated that their agenda for the Middle East would be a slow and tedious process without a new "Pearl Harbor" type event. So all of this was written over a decade ago, but the actual planning goes back several decades. The agenda has always been to take over the Middle East, install puppet governments like we now have in Iraq, control all the oil in the region, and standardize the entire region under the same fiat money system which controls the West. Muslim terrorism has been the excuse to launch this long-term agenda, and fear is the number one method governments use to get people behind them, believing it's in their best interests.
Perhaps it got too much bad press in the alternative media, so they have become more active in other thinktanks which can accomplish the exact same goals and have nearly identical member rosters? This must have been the first thought you had when you woke up this morning.