Not counting any shows that did not have an actual announcer, how many shows can you think of that had the host in an active on-camera role in the intro before being introduced by the announcer? Here are some:
Double Dare (all Nickelodeon versions)
Think Fast (Michael Carrington, not sure about Skip Lackey)
Born Lucky
Debt
It Takes Two (1997 Dick Clark version)
Win Ben Stein's Money