Already posted this link over on the Project Support blog – but wanted to be sure no one missed it. The brand new Project Online getting started articles are at http://office.microsoft.com/en-us/project-server-help/get-started-with-project-online-HA102858793.aspx and these walk you through the Project Online sign-up, add people and create projects. Thanks to Sonia and all the folks in the review cycle who helped make this happen!
The link above to the getting started article is broken as of 9/30/2014
Thanks Kelly - we are working on it. Some new links and redirects aren't hitting them quite right.