Article written for the publisher of my book, Drupal 7: Visual QuickStart Guide. I wrote it at a time when Drupal 7 seemed primed for imminent release, but it ended up taking a year more. The article is still fairly accurate, though.
I started writing it in 2009, then shelved it, then revised extensively in late 2010 as the pre-release software changed substantially. It was officially published about three weeks before Drupal 7's release.