It's interesting to note how much has happened in the short 891 days since that previous discussion occurred in mid 2012. At that point, the space shuttle fleet was retired but SpaceX hadn't yet flown a commercial resupply mission to the ISS. Curiosity hadn't yet landed on Mars. Rosetta/Philae arriving at their comet, etc. I'm sure someone can come up with a more complete timeline, but I've been following space exploration as a layman for a number of years and these last couple of years have been some of the most exciting in quite awhile.