One thing I concluded from this is, from now on, there is no point making 3D apps without shaders less than 1.4 shader model... Some would say even 2.0.
That conclusion is only valid if you're going to be distributing said 3D app via Steam. If said 3D app is going to be used in schools or government institutions, or if it's going to be sold to casual gamers, your demographic is going to be completely different from Steam. I only mention this because people do routinely draw conclusions from Steam as though the average Steam user were the average computer user. Steam is very much a hardcore gaming portal.