I really don't know if they'll want to handle a whole bunch of re-applications. They might have a similar situation where the law would give USCIS a certain number of days to figure out a way to easily convert DACA recipients into legal residents.
I have a feeling that the Dream Act will be re-written just to tie around DACA.
They will probably say something like: "Look-- these students have been contributing $X to the economy with their (list degrees here) degrees, and they deserve to keep working and contributing to the nation. These students have proven to be assets to the country, and we will only be keeping the brightest of students with the Dream Act"..... etc.
So basically, if you don't apply for deferred action now, it might be a nightmare later on. They will probably keep an eye on us until the Dream Act comes out, and set new requirements based on their observations on us.