People keep citing technology as a reason that the classroom will be obsolete, and following the basic premise that you've laid out: the lecture is canned, I could watch a video and get the same result. (I'm not ignoring the rest of your points, but I do want to respond to that one.)
The current trend in educational technology is just the opposite - it's an attempt to make the dialog more symmetric (note: I did not say completely symmetric, and it should not be!) Student response systems (aka Clickers) allow instructors to get a more real-time feedback about how well a class has understood a topic, and allows us to adjust our delivery/explanation approach, and reallocate time from mastered to unmastered topics. Online homework systems help large classes still receive feedback regarding their progression through the topic, and 'shrink' the size of the class (my 140 person class gets interaction that feels more like a 40 person class).
That's not to say that we've reached a new steady state, and it's not an advocacy for large class sizes. However, I hope that these passing examples point out that when properly used, technology can help make the classroom more relevant than a video file. There will certainly be a growing-in period for the technologies and their uses to mature, and I do think we're in the early stages of that now, but I see a lot of faculty growing beyond 'PowerPointless' presentations and that's a good start!