Going from PBI to EWR for the first time as a silver elite, I was really not expecting an upgrade to first after reading all the comments on this board about upgrade percentages. I received an e-mail stating my one pass elite upgrade had been processed. Once boarded, I was shocked that the plane appeared full but there were four empty first class seats! On the return, we were on a 757-200 with BF configuration. Again, the flight appeared full. I received the e-mail once again about the upgrade for the return flight. There were eight empty FC seats! I kept thinking "there can't possibly be no other elites on this plane". Is it common for that many seats to be left empty in FC? Just curious.