Getting a new developer up to speed is one of those 80/20 tasks: there is an easy 80% that goes quickly, and a hard 20% that takes longer. The easy part is the big picture: what tools the team uses, where the source is, what the build process involves.
The hard part is in the details. Coding standards. Preferred practices. How to deal with the inevitable idiosyncratic aspects of any software development process that has been running for more than week.