Ian Morris on "why the west rules", which seems to be a provocative title for an interesting book on historical geographical trends and their projection into the future: http://www.youtube.com/watch?v=tvkHiL-H2io. He starts talking about the future at minute 27 and basically concludes that a singularity scenario is one of two possibilities for the 21st century, the other being collapse. Nothing new, but encouraging to see this increasingly in the mainstream.
Haven't watched the video, but my vague understanding is that "business is usual" depends on unsustainable rates of growth, pointing toward collapse, and includes constant progress in AI-related technology, pointing toward singularity. The potential vagueness of the boundary between business as usual and collapse might be a problem in talking about which is more likely, though.
I wonder whether a continual rear-guard action forestalling collapse would be considered "business as usual" or not. I suspect yes, and that someone sufficiently cynical would say this is what is already happening.
I can imagine alternatives that can't be considered either singularity, collapse, or business-as-usual -- a resource-based economy, for example -- but I don't consider them any more likely than either of the first two. Political trends strongly support collapse.