A new geoengineering research program has been established at the Tyndall Center at the University of East Anglia. This will surely go down as a milestone.  The institute is named after the scientist that identified the greenhouse effect is now forming a geoengineering institute,  and the Tyndal Center has been viewed as amongst the more conservative (cautious) thinkers in this area.

"The GeoEngineering Assessment and Research initiative (Gear) has now been set up at UEA to assess the projects that have been suggested. Among the geoengineering solutions that have been proposed are putting mirrors into orbit to reflect sunlight away from Earth, and encouraging the growth of plankton by pouring nutrients into the oceans.

“An increasing number of scientists are talking about Plan B now, the big, global geoengineering things,” Professor Davies said. “That's one of the reasons we've set up this centre - not that we think many of the aspects are sensible but because we think it's necessary to assess them.”

Jamais Cascio also has some very insightful commentary on this.