Quick thoughts on the deadline deals -
Cliff Lee will probably have the biggest playoff impact of any player added near the deadline. No, he's not as great as Roy Halladay, but he's roughly 90% as good, costs less money, and probably cost a lot less in prospects. Lee makes the Phills a much tougher team in the playoffs and the clear favorites in the NL East next year. And the organization didn't have to part with any of their 3 top prospects (according to Baseball America). Great move.
Loser: Blue Jays
It's always hard to know how much to believe about all the rumored deals, but it seems like the Blue Jays overplayed their hand in the Halladay negotiations. The Indians were probably right to start rebuilding, but there's a reasonable argument that they should've kept Lee & Martinez and made a run in a weak division next season. On the other hand, there's no reason to think the Blue Jays can compete in the toughest division in baseball next year (the last year of Halladay's contract). They may still be able to pull off a better deal in the offseason, but for now, it seems that they blew their chance to start building for the future.
Brett Wallace was the only prospect in Baseball America's recent top 25 included in any of the deadline deals. It's impressive that the A's got him in exchange for two months of a player having a mediocre season. The A's pretty much had to deal Holliday (it might've been risky to offer him arbitration) and didn't seem to have a lot of takers, but still managed to get a very good package in return. I still think it was a mistake for the A's to acquire Holliday in the first place, but Billy Beane still managed to do okay in the end.
Winner: White Sox
Special props to Ken Williams, who always seems to pull off surprising trades. Jake Peavy may not pitch again this year, but he's a great pickup for the next 2-3 years of his contract and there's a decent chance he'll return in September. Peavy may not improve Chicago's odds of reaching the playoffs, but if they do make it (probably a 30% chance right now), he could be a big help.