I'm working on building a website in Rails and ran across this great site with a bunch of free screencasts related to Ruby on Rails.
A couple years ago I started playing with Rails version 1. Rails 2.x is the latest and a lot of things the 1.x commands don't work in 2.x. The one I ran into last night was rails migrate. It is now rails db:migrate. I'm sure there will be a few more gotchas like this, but in general 2.x seems to be worth it, even if a lot of the guides out there on the web are a bit out of date.
rails migrate becomes rails db:migrateBTW, if you like Railscasts, there is a donate link. I dropped$5 in the tip jar.
MySQL becomes sqlite3