The third team on my list of teams to root for now that the Mariners are definitely out of the running is...
...the San Diego Padres
They are my original home town team, as I was born there and lived there for the first several years of my life. There are a few reasons for everyone else to root for them, too, though.
They made the World Series in 1998 and said "OWWWWW" as the skankees brutalized and swept them in 4 short, terrifying games. They have yet to make the playoffs since, and here's hoping this year's the year.
The reasons start with PETCO Park. Okay, this is only a good reason if you want teams with a new park to do well. In recent years, teams with new parks have had swells in attendance for the first few years, but unless there was a quality product on the field, numbers dwindled after a few years. In order to keep the fans coming, San Diego needs to do well within the next few years.
Another reason is the improved lineup: gone is radical Rey, in is Khalil Greene, a rookie shortstop sensation. The outfield is full of pop, thanks to the bat of Brian Giles. Although some injuries have hurt them, specifically Klesko, and Payton early on, and more recently David Wells and Jake Peavy, the Padres remain in contention for the NL West.
If you're not already on the Dodgers bandwagon, either because of the early season success, or because (like me) you are a fan of Paul DePodesta, then the Padres are a great underdog pick to win the NL West. Many pundits predicted that the Diamondbacks or Giants would win. Many also picked the Rockies to be the "underdog" winner, but without a plan or any real talent beyond Todd Helton (currently injured) and the Coors Effect TM, the Rockies probably won't win any time soon.
So, when you're watching NL West teams, cheer for Barry, but realize the Giants wont go anywhere without somebody else of identifiable value outside of Schmidt (at least until his arm falls off -- the guy is injured, has surgery on his elbow, comes back and within a few starts is throwing 140+ pitches!). The division will probably come down to a race between the Padres and Dodgers, so if you have no current allegiences, maybe you should jump on the Padres wagon before we run out of space.