Few days earlier I was happy to see this talk given by Barbara Liskov:
Few days earlier I submitted a paper to ESWC10 ( found here , titled "Flexible Ranking and Matchmaking for Semantic Service Discovery"), which happened to include a reference to Liskov and her well known substitution principle (the bottom side of the 3rd page).
It was not a big deal, just "common sense" reiterated. As you will notice from the talk above, though, at the 70ies this kind of "common sense" we take for granted today, was debatable and unclear then -- just as debatable was whether the goto statement was evil or not!
One thing that impressed me most in that talk was a photo that Barbara shared with the audience, from the 70ies. I had never saw her young!
I will leave the photo uncommented - it speaks for itself. -edit: well, I commented it after all, see below :)