There are flaws with every team.
Mets- Starting pitching a major question mark, and the lost of Sanchez really hurts that bullpen.
Red Sox- Starting pitching is a mess right now. They are also hit with some injuries on offense as well (Nixon, Varitek, etc.)
Yankees- Starting pitching is very inconsistent. There are only 2 dependable starters.
White Sox- Starting pitching is awful right now. The team has played very poorly since the AS Break.
Twins- They have little offense and will need Liriano to keep up this ridiculous pace to even have a shot at making the playoffs.
Athletics- Decent pitching but absolutely no offense.
Angels- Very good pitching but no offense.
Rangers- Great offense but little pitching.
Reds- Improved their bullpen, but I still don't see them going far, if anywhere. I don't trust their starting pitching.
Cardinals- Just appear to be a mediocre team. Not awful in any one area, but not overly great, either. Might be the 2nd best bet in the NL though.
Braves- I don't see it. They lack the bullpen and SP depth.
Astros- Terrible offense.
I noticed you left out the team with the best record in the majors, the Detroit Tigers. Probably just a mistake. To be quite honest, there is no team to beat here. The Mets should be able to dominate the National League, but when compared to the AL, they are thrown right into the same category as the Yankees, Red Sox, White Sox, Tigers, etc.
Very difficult to say right now. IF Randy Johnson can pitch decently, and the Yankees get some pieces back healthy (Matsui, Cano, Dotel, Sheffield) then I feel they have a great chance to win it all. The Mets should be in the W.S. as well, because there really isn't anyone to stop them in the NL. I suppose they are the best bets right now to win it, since they are basically guarenteed a playoff birth and won't have to face a dominant team until the World Series.