I think I would highlight the following features: * Interactions: last time I checked RevealJS does not offer any kind of interactions. It tends to be hosted as static HTML files, so you need some kind of logic to process interactions * Control: Although I believe slides.com allows phone as remote, a user-hosted reveal JS presentation would not. * Ease of use - many users don't want to edit HTML files. Even I didn't want to keep editing HTML files.

However, I agree that RevealJS is great and I did use it in my lectures after I gave up powerpoint!

My thoughts exactly. RevealJS is missing some of the features that 2sli.de is advertising, but the foundation (e.g. socket.io, multiplex-plugin) to develop these plugins for revealjs is already there.