I haven't heard anything since the announcement. IMDB's last update was in January. It's not just Ron Howard though--it's also a bunch of the people who worked on the Apollo 13 film, which seems like a very good fit.

Unlike a lot of folks, I liked the second part of Seveneves, but I won't miss it if they cut it from the film. I don't even know how they'll fit the whole first part in without a 3.5 hour running time.