Ask HN: What do you look for when choosing a conference?

A few days ago I put together a simple site with a list of DevOps conferences and some sorting buttons http://www.gotodevops.org/. I've overwhelmed by the positive feedback I received and contribution on GitHub from many people.

Now, I'd like to improve the website and make it even more useful for people who are searching for conferences. Current list of features to add:

- searchable list of speakers and presentations

- indicate if the conference will record / stream the presentations

- what weather can you expect during the conference

- rating / experience from the past visitors

What else do you look for when choosing which conference to attend?