Has EVERY VOTE been counted?

I do not consider myself an Intelligent man, however I find it difficult to believe that EVERY vote in the United States has been counted. EXAMPLE: In California where I voted by Provisional Ballot, there are several propositions which have neither ped or failed because there are a great number of Provisional Ballots that have not yet been counted. To me this means that my ballot, which contains my vote for President of the United States may have not yet been seen and recorded. This brings me to a hypothetical question. What happens in two or three days, or a week or two weeks or however long it takes until EVERY Absentee Ballot, EVERY Provisional Ballot in the ENTIRE United States has been seen and "counted", the results change. Would John McCain then be the President Elect even though he has conceded the race? Or have they simply stopped counting because the results have been announced?