Even if you get Odom back, you have holes.
PG is a worry for you - Fish will slow down one day very soon given that he's turning 35. Brown is nice, but is he ready to run the team?
Losing Ariza is a blow - he was clutch for you last year, and he was the guy you threw at fast guards like Parker and Paul. Who you gonna throw at them now?
Your bench, besides Odom, is thin.
Kobe has over 1100 games on his legs.
Bynum is yet to come on as expected.
Nothing is a certainty.
Is it any more certain for anyone else? No. But the Spurs just added at least 3 big upgrades (RJ, Dice, Blair) that fit perfectly into holes from last year. The Mavs' pieces look less well suited to each other, but I can see that as a very powerful team if everything clicks at the right time.
IMHO, any of the Lakers, Spurs, or Mavs could be the Wests' representative in the Finals next year. It'll certainly be a closer run thing than this year unless injuries derail these teams.