ANN threads are effective for sure. But i am not sure about bounty campaigns. There are so many bounty hunters they open useless social media accounts to get more free tokens. A more professional advertising strategies are a must for icos.
If running a project with Bounty it is also very effective, because there are also many participants who join, including ANN, other media suggested through ANN are also very helpful to develop the ICO to be built. But all of that depends on the participants to be more diligent in developing the ICO.