I have seen almost all of the ICO's going for ANN thread first and announcing BOUNTY later at least after a week. But some have gone for bounty first and ANN later. Is it necessary to announce ANN first or is it some kind of strategy?
Ann thread is important. Beside of their site and whitepapers. It contains most of the info about the campaign you are joining. it shows that the project is serious about what they're doing.