[Steve Turner 1/19/2007]
I created a new subfolder in my sandbox for a web project, but there's no icon or link to allow me to submit the new folder and promote it to the sandbox. To do this, I had to go to the top level of the web project and choose 'Submit All' for the sandbox. Clearly you may need to submit a new folder without submitting everything else in the sandbox.
I'll test this again when we get hold of the Beta.