(Updated November 10, 2011 - Updated information about file actions. Thank you Patrick Thurmond!)
(Updated June 4, 2011 - File Handler Compatibility with Migrate 2.1)
(Updated June 8, 2011 - Image to show how to write out your destination field names)
Updated August 29, 2012: I wrote out a blog post on the new image/file handler changes from Migrate 2.4+ a few weeks ago which you can read about here. I've not updated this blog post with those changes so take a bit of what you learn from these blog posts, and add in all the things from the new one for anything file related (or just look at the new one since I link out to the new reference codebase from there as well). and hopefully it helps :)
Its been a while since I wrote about using the migrate module to migrate content from various sources. The last time, I covered migrating users into Drupal and this time, I will write out how to migrate content into drupal as nodes. Because the migrate module is so flexible, it makes doing such things quite easy.