As of the latest version of Chatter Mobile(v4.2), you can now include VF tabs in the app. Mark the VF page as Available to Mobile apps and create a tab that uses that page. Then go to Administer>Mobile Administration; you’ll find a new option called Mobile Navigation. This lets us rearrange “stage left” in the Chatter Mobile app. We can add and remove standard components and also add our mobile enabled Visualforce tabs here.
Once you are all done, fire up Chatter Mobile!
I wrote a blog post with a bit more info: http://www.verticalcoder.com/2013/11/06/chatter-mobile-and-visualforce/
After playing around with Chatter Mobile more, I've also realized you can embed mobile pages on records by editing the page layout and dragging mobile ready pages to the Mobile Cards section of the page layout.