SpaceX finally did it. They launched a Falcon 9 rocket, went into space-ish, reversed the engines, and landed back on Earth. This is important because this will significantly reduce the cost of putting things into space, but also resupplying the things we already have in space.
In terms of rocket-propelled launches, this is a big step forward.
We still haven't really solved the problem of space flight. Even with Falcon 9, we are still using a 541 ton rocket to send 13 tons into space (or 4 tons into geosynchronous orbit). That means that 97.5% of the rocket is either fuel or engines. The real dream for a space geek like me is still for us to develop rockets that aren't rockets at all.
But, for now, SpaceX's Falcon 9 is amazing. The old Space Shuttles cost a staggering $450 million to launch, on average. Falcon 9 is set to cost $61 million per launch, with its bigger brother Falcon Heavy set to cost $90 million per launch.
That's some serious cost optimization.
Note: You can watch the full launch and landing webcast here: https://www.youtube.com/watch?v=O5bTbVbe4e4