I would agree for a talk you should optimize for the primary medium, being live presenting. Sure if you want to spread the word you can create other content with the same topic name, like a good blog post, to help you get the message out. There's noting worse than crappy over texted slides where I attend and am thinking, I could have just stayed home and read the slides.

Apparently there was a classic talk by Dr Nic from Engine Yard who also does stand up comedy, the speaker didn't show up for some reason so Dr Nic jumped up and gave the talk cause he could just read the slides like everyone else. (disclaimer: wasn't there so facts may vary)