I'm not sure what could be done that would be dangerous in the name of "ushering in the singularity." The worst plausible scenario is that we put money into research avenues that don't pan out. But that happens all the time anyways. The real worst case scenario is that someone gets too afraid of AI and goes all Sarah Connor. But that's not a likely scenario especially because most of the people who take the Singularity idea seriously are people who are generally optimistic about the long-term trends.