Slideshare is an interesting idea. Here's a slide showing answers to criticisms of Ruby: http://www.slideshare.net/vishnu/the-top-10-reasons-the-ruby-programming-language-sucks/
But it's SO slow! Not Ruby- but the fetch every single click to Amazon's s3 data service to get the next page. I'd like to see the rest of the slides, but I just don't have time to wait a couple of seconds+ for every single slide.