Adrian Gonzalez just hit his 21st homer against the Phils. 
Gonzalez is nasty. What is more is that he is crushing home runs at Petco, one of the most spacious parks out there. It wouldn't be out of the question for him to reach 60 HRs this season.
Another interesting storyline out there is the strength of Detroit's starting pitching. At the beginning of the season I thought it was going to be a mess up there. Justin Verlander has got his stuff together and has settled in as the SO machine everyone thought he would be when he was drafted. He now struck at least 8 batters in all but 2 games, over 10 batters in 3 games. He is currently averaging the fastest fastball in the league at 95.5 MPH.
Another guy that is throwing some serious heat (94.4 avg fastball) up there is Edwin Jackson. The Tigers got him in a trade from the Rays, who thought that he would never live up to the hype he generated as a young pitcher. Well, he is living up to it. He has become more economical with his pitches and is going deeper in games. His WHIP is currently sitting at 1.04 and the ERA is at 2.30. Jackson is just starting to blossom and should be a top of the rotation guy for years to come. Detroit got a steal on this one.
Then there is Rick Porcello, the youngest pitcher in the league currently and one of the leading candidates for ROY. He hasn't been going too deep into games yet, but he has been giving his team a great chance to win each game he pitches in. He has only let up 5 runs in his last 5 games. He has been relying on his fastball a lot and has been getting a bit of luck, but he should continue to improve as he gains maturity and experience.
And then there is the interesting case of Dontrelle Willis. Traded from the Marlins and signed to a huge extension by the Tigers, only to seemingly lose all ability to pitch. He was DL'ed earlier in the season because of anxiety order, but is now back with the big league. He has struggled in two of his four outings, but has showed promise in the fact that he has returned to the mechanics of old. His fastball velocity is down and the walks are still troubling, but Willis seems to be on the path to redemption.
Lastly, there is Armando Galaragga. He was a guy that emerged out of nowhere last season to have a great year. He was probably the one guy on the staff no one was worried about and in an act of irony he is struggling the most. He has been much more hittable this year and teams have gotten to him early. He is letting the long ball up more and is walking batters without discrimination. I have a feeling Galaragga will bounce back in the second half of the season, but wouldn't be surprised if he continues to struggle and even loses his spot to Bonderman when he returns.
Detroit has a good rotation that should be in place for the next few years. I have caught a couple games of theirs and it has been a pleasure to watch good pitching. Unfortunately for the Tigers, there bats are as heavy as they have been in the past and they will have to now rely on their rotation to bring in the Ws.
EDIT: oops, posted this in the wrong section; Ironically ESPN had an article about this exact same subject today, they must be stealing ideas for articles from my posts
http://sports.espn.go.com/mlb/columns/story?columnist=crasnick_jerry&id=4221583