News that longtime San Francisco 49ers long-snapper Brian Jennings received his release Saturday marked the end of a special-teams era in the NFC West.Jennings, 36, had been unerringly consistent since 2000 and was the final 49ers player remaining from the Steve Mariucci coaching era. But with the 49ers pinching salary-cap dollars with an eye toward continued roster building, they decided undrafted rookie free agent Kevin McDermott was a better value.