For immigration purposes you are a non-resident since you have not been granted permanent residence as of yet. For tax purposes you are a resident since you have no intention of departing the United States.
While this answer is provided by a Florida Bar Certified Expert in Immigration and Nationality Law, it is for general information purposes only and an attorney/client relationship is neither intended nor created. You should seek out qualified counsel to review your case and provide you with advice specific to your situation. Call +1-561-478-5353 to schedule a consultation with Mr. Devore.
This is not a simple question and should should discuss with your tax advisor. If you would like to read up on the issue please see http://www.irs.gov/taxtopics/tc851.html and Publication 519, U.S. Tax Guide for Aliens.