Google Drive is the new home for all your Google Docs. The blog post included the news that if you haven't transitioned yet you will see a prompt to transition the next time you visit Google Docs. You can choose to continue to use the "old look" for a while by selecting that option in the settings menu, but that option will eventually go away too.
If you're looking for a guide to Google Drive, I published one in May. It is embedded below.
Google Drive and Docs for Teachers 2012