Google Docs looks... smashing. The new start page has a sidebar that lets you filter the documents by tag (renamed to folder in the interface), by type or by collaborator. And you can now see all your files by default, not only the documents or spreadsheets active in the last 30 days.
The folders can now have descriptions and you can send a document to a folder by using drag and drop.
Google removed the option to sort the files by name or author, so the only available sort option is by date.
The search box includes an autocomplete feature for file names, folders, authors. To find the documents or spreadsheets that actually contain your text, you'll have to click on the search button.
The new interface is a huge step forward and makes room for more types of documents and better ways to share your files.