Baseball: Longest Streaks - On or Against?

What's a better move, take the longest streak going in each league and bet for it to continue or to reverse? (Doesn't matter winning or losing streak, just the longest)

Reverse - winning teams are due to lose more than losing teams are due to win - by summer, many teams will be "tanking." Someone will disagree with me but that's the way I see it - maybe it depends how long you can fade a streak - Blue Jays were supposed to be good this year, but just lost 9 straight. I think you could consider fading a streak after a team reaches a certain number (somewhere between 6 and 10?), but be careful of very bad teams - I think Royals lost 15 straight last year or year before.