What’s the big deal?

Photo of Larry Lessig, via his site.Lessig (left) writes:

huge and important news: free licenses upheld

So for non-lawgeeks, this won’t seem important. But trust me, this is huge. … the Court of Appeals for the Federal Circuit (THE “IP” court in the US) has upheld a free (ok, they call them “open source”) copyright license, explicitly pointing to the work of Creative Commons and others. … the Court has held that free licenses such as the CC licenses set conditions … on the use of copyrighted work. When you violate the condition, the license disappears, meaning you’re simply a copyright infringer …

The decision in Jacobsen v Katzer is excellent news, to be sure; but isn’t it obvious? It may be “huge”, in the sense that this is the first time that a court has actually said this; but this has always seemed obvious to me (which is why I use a Creative Commons licence on this site). What am I missing?