Are the qualifications for permanent residence status defined by statute , as with citizenship qualifications, or are those subject to change at the whim of the sitting POTUS and governed by EOs? Serious question.
I generally do not do "real" immigration (I've done some work permit stuff for clients and an interesting coram nobis case), but this is my understanding: the qualifications for PR status is statutory and cannot be altered. Some time a few years ago, they made it so that if you are here illegally, but married to a US citizen, you had to leave the country while they processed your PR application. There was a "hardship" exception, but under GWB, it was a high hurdle. It took more than just having family here.
So, some people stayed here as illegals because they didn't think they could get the hardship status. Oh, and I think if you didn't leave, not only could you not come back, if you did come back and got caught, you had to leave for 10 years. I may have that wrong, though.
Anyway, it SOUNDS like (this is speculation), Obama is saying that just having legal family here is enough to get "hardship" status, or that his DOJ won't fight a petition for hardship status under certain criteria. This will let people stay who otherwise would have had to leave.
(For some reason, I don't think the "make them leave" thing was labeled "deportation." I can't remember the phrase used - something like "voluntary removal" that wasn't particularly voluntary.)
Anyway, that's my understanding. The qualifications don't change, but the interpretation of the exceptions/defenses can.