It was a few years before we saw a derivative of the human-computer interaction present in Hypercard come out that changed the world in the form of NCSA Mosaic. I'm guessing Scoble was moved to tears because he feels the seeds of something great is going to be released on March 3 in that it will open up a world of possibilities for some other group or individual to take the possibilities to a higher level (in much the same way Mosaic took the concepts of Hypercard to the next level). I highly doubt we are going to benefit immediately from whatever we see.
I also think Scoble has hit upon a great point: today's overwhelmingly profit driven model for creating software sometimes misses the beauty in creating something for the pure joy of creation (probably an ironic statement given the fact that this is a VC-based message board). Part of me is saying this because one of the projects I'm working on frequently hits the question: "It's a nice idea but how is it going to make money?" (so I suppose my personal biases are showing through here in this remark).
I remember staying up to 4am with my college roommate, the night we found installed NCSA Mosaic for the first time. Of course, we regret not becoming wealthy by creating a free email service or whatever (it was wide open) but ce la vie.