Thanks for posting this. I’m one of the core developers on Velocity and also the author of the book.
You’re right about calling out the documentation aspect of Velocity. We recently rewrote http://velocity.meteor.com to make it simpler for people to get started and we are also in the process of considating our docs. I’ve already started doing this for Meteor Cucumber, which you can see here:
The rest of the frameworks will soon follow this approach.
As a new user, I understand that it’s hard to get all the concepts but you should also know that Velocity itself has never stopped being worked on since last June and is still very active. You can check atmosphere and github and see some healthy numbers for usage and updated. Meteor also announced that Velocity will be integrated into the core in the coming releases so you would be right in using it.
The book content is up to date with the latest release of Velocity. The chapters have been a little slow over the last month but I have been working on getting all the material ready for it. If you would like an early peek at the example app that uses all the concepts, you can check:
Until the docs are fully updated, I suggest diving in and seeking out help here. We are always listening and ready to work with people.
Of course there are only a small group of us that do this project for free and we could really use all the help we can get, so if you or anyone reading this would like to do something about this problem and help us with documenting, we would welcome the efforts.