Marseille might be a good call. Lyon have definitely gotten weaker with a few players leaving such as Malouda, Abidal, and Tiago. They also struggled at the end of the season, especially up front. Problem is they have so much money to spend.
Also, the loss of Ribery is going to hurt Marseille. So, they need to invest wisely.
I don't like the odds on Bayern. Their 3 rivals have lost key players, whereas they've spent alot of money on some real talent. But, you don't know how that will affect the balance of the team or whether they'll be able to really gel together.
Man Utd obviously have a great chance, and if they get Tevez, they'll be even better. They've managed to get alot stronger in terms of squad depth, and the signing of Hargreaves is a very good one as it'll give them another dimension to their play. Chelsea will be a huge threat this season as they've reinforced the defence, and got a couple of shrewd signings in Pizarro and Malouda. Robben would be a big loss though. They also really need a rightback. They could struggle in January as the African Nations Cup takes place so they'll lose their two best players in Drogba and Essien. Liverpool need to sign a winger, but they've made some good purchases. They've got a good squad.
Arsenal need some more signings, possibly a bit of experience.
As for La Liga - Valencia are signing alot of talented Spanish players. They were wrecked by injuries last season. They've got a decent chance. No one knows what team Madrid will line up with next season. Sevilla need to keep some of their top players especially Kanoute and Alves. Their president does have money to invest. It's hard to see past Barcelona with their signings. The defence is alot better with Milito at the back, and Abidal. They've strengthened midfield with Yaya Toure. But the big one is obviously the signing of Henry. They suffered with bad defending last year, and big injuries to Messi and Eto'o. They are rightful favourites this year, as no other team has as much talent as they do.