Jon Ying on the Dropbox blog:
You now can choose which folders get downloaded to which computers.
I have been using Dropbox for a long time now – I think since you could get it. This is a great release and I have had no problems with the beta builds of it. Selective Sync has been a top requested feature for a very long time – it is implemented very well.
BTW if you are not a Dropbox user and would like to sign up – using this link will give us both an extra 250mb, even if you only sign up for the free account.