They did lose Juninho and Omar Gonzalez might miss the season with an ACL injury, but yeah, their attack has to be considered the best in the league.
Beckham's age renders him merely a playmaker... much like Marquez. Guy is vastly overrated at this stage. Get Rafa on his game and he can bring most if not everything Beckham brings but with better defense.
Donovan is the big difference. Keane is younger/healthier than Henry, will play more games but I give Henry the edge in quality. We don't really have anyone to match Donovan. Lindpere is good though.