Previously, iWork.com let you share Keynote '09, Pages '09, or Numbers '09 documents via a browser with invited members of a team. Now, you can create a public link that allows anyone to see your files, no invitation necessary. It couldn't be easier to set up: With the document open, select "Public" and then "Show public URL." From there you just copy and paste. You can also track the number of views your publicly shared documents receive.
The other addition is improved iPhone and iPod touch support. The login interface is much improved as well as the list of documents. I've got a number of large Keynote slide shows up there, and not all of them fit on my iPhone's screen, but they were easy to flick through.
It's a nice update to a service we haven't heard much about lately. To share a document via iWork.com, select "Share via iWork.com" from the share menu of a Keynote '09, Pages '09, or Numbers '09 document.