This is tricky; I'm writing this on Thursday, while waiting with bated breath to see if the SpaceX Dragon capsule will successfully dock with the International Space Station on Friday. Even after the success of SpaceShipOne in winning the Ansari X Prize in 2004, on some level it's still weird to me to watch the development of a commercial space flight industry after so many years when any space flight that happened was exclusively a governmental endeavor.
The list of commercial spaceflight companies (courtesy of Wikipedia) is longer than I'd realized, with most of the crew and transport vehicle projects still in development (except for Dragon, which is operational) and a larger proportion of the launch vehicle projects operational. Which is a very long-winded way of saying, holy cow! Privately produced space vehicles! It may not be personal jet packs, but it still delights my little technology-loving soul.
I also happen to think that these new space vehicles and launch platforms are building on the vast amount of data and know-how acquired over the decades as we learned how to send things and people into space and how to bring them back safely. When you consider how little we knew about what space was like and what kind of conditions were involved in breaking free of Earth's gravity, surviving in space, and then coming back to land, the people who have been diligently working in the space programs have created an impressive body of knowledge. The aim of the commercial spaceflight companies is to develop technologies and vehicles that will let us move people and cargo into and out of space efficiently, safely, and far more cheaply.
There are two aspects of this that I find most interesting. The first is the efforts involved in creating equipment such as the Falcon 9 rocket and the Dragon spacecraft. That's a lot of intense, multidisciplinary design right there, and with anything this experimental, that means the need to measure lots and lots of parameters, both during manufacturing and prototyping and during flight. Hello to new sensing and DA techniques! The second is in how commercial spaceflight can be used. What can we learn if we can perform a larger number of space-based experiments?
At this point, my fingers are crossed that all goes well and Dragon will successfully dock with the ISS. Kudos to all involved at NASA and SpaceX and may this be the first in a long line of successful missions.