There were a record tieing (1988 Midsummer Classic) thirty first-time All-Star players on the official rosters and thirty-two total if you count (Major League Baseball does not) Shawn Chacon & Marcus Giles who were replaced on the National League roster due to injuries.

Did you know that of the seventy players selected to the 2003 All-Star squads, forty-nine were from the United States, six were from the Dominican Republic, five were from Puerto Rico, three were from Japan, three were from Venezuela, & one (each) from Canada, Mexico, Colombia & Curacao?
This was the first All-Star Game "where it counted" (the winner was awarded home field advantage during the World Series), the first with a Colorado Rockies home run (Todd Helton), the first for thirty first-time players (see fact one above) and the first in U.S. Cellular Field (but the fourth in Comiskey Park).