Why care?
It's just one other problem that may eventually become a reality, what scares people is that they see the causes every day, cars, buses, computers, power-stations (all arguable causes mind, after all it may not even be us apparently :roll:). Each time (thanks to mass media, gotta love it) they think about it, even if only subconsciously . At the end of the day I'd take slow eventual (and perhaps possibly survivable) "climate change" over short but most certainly terminal meteor strike or massive volcano eruption or whatever of the thousands of things that could blip us out of the universe in a flash.
I suppose sure, we caused it (arguably) but we cause a lot of things extinction of hundreds of species, the culling of entire forests, etc.
At the end of the day if your so worried why are you sat at your computer now and not out planting trees or whatever else people who care do..