In my generation, the last true pennant race was 1993, when the Braves and Giants were clawing for the NLWest, only to see the Giants with their 103 wins miss out on the postseason.
The next year, Bud Selig decides to give more teams a chance to head to the postseason by implementing the Wild Card, which would be the best team in the National League or American League that didn't win their division.
Since that implemention, baseball in the last decade-and-a-half saw a lot of thrilling pennant races.
Here's five of the best in the National League since the Wild Card came into play:
2008 (Milwaukee Brewers and New York Mets) The New York Mets, who lost the NLEast in 2007 on the final day of the season to the Phillies were in a virtual tie with the Milwaukee Brewers on the final day of the season. For the Mets, the final day of the season in 2008 was also the last day baseball was to be played in Shea Stadium while the Brewers had their rivals to the south, the Chicago Cubs at Miller Park with a crowd ready to erupt. All it took was Ryan Braun's homer in the eighth inning and the Marlins beating the Mets to give Milwaukee its first postseason appearance in 26 seasons.
1998 (San Francisco, New York Mets, and Chicago Cubs) If not for a dropped fly ball, we would have never heard of Brant Brown, who made the misfortune of playing for the Chicago Cubs that season. Brown dropped a routine fly ball with the sunlight distracting him, giving the Brewers the win and the Cubs tied for the Wild Card lead with the Mets. However, the Mets would fade down the stretch and the Giants would tie with the Cubs on the final day of the '98 season to play a one-game playoff at Wrigley Field, which would be won by the Cubs, giving their first clinch of any kind at Wrigley since 1938.
2007 Colorado Rockies and San Diego Padres Colorado, which had Garrett Atkins, Todd Helton, and a guy named Matt Holliday in their lineup, came out of nowhere in mid-September, winning 14 of their last 15 games and forcing a playoff with the Padres, which completed probably the second biggest collapse in 2007 thanks to Matt Holliday's slide, which is still debatable in San Diego.
2004 Chicago Cubs and Houston Astros After coming within five outs of their first World Series in 58 years in 2003, the Cubs looked to contend for the NLCentral with the Cardinals and Astros. While the Cardinals ran away with the Central, the Cubs' only hope in reaching postseason was by winning the Wild Card. In Houston, the Astros fire Jimy Williams and replaces him with Phil Garner, who guides the team to an improbable postseason berth due in part to the Cubs' foldaroo in the final weeks of the 2004 season.
1999 Cincinnati Reds and New York Mets The Reds that season had one of the best road records in the National League. Led by Sean Casey, Barry Larkin, and Mike Cameron, it seemed as if the Reds were going to make the playoffs for the second time in five years. However that was not to be as the Mets defeated the Reds in a one-game playoff en route to the 1999 NLCS and the Reds' fortunes sank after the devastating loss in the one-game playoff. Since 1999, the Mets have made the postseason three more times including that season and the Reds have not.
So there you have it. Let the debating begin.