Kobe isn't mentioned, because he shouldn't be mentioned this year. He missed a lot of games, and his team completely fell off the map.
But yes, you're right, Kobe is just as worthy as Iverson or LeBron, but that is more because of the hype for both of those players being out of control. None of these three deserve MVP, not even close. Of the players on bad teams, Garnett is easily the best.
1. Shaq - He has been healthy the whole year and has his team in 1st place in his conference.
2. Tim Duncan - Same resume as Shaq, in a better conference with better numbers and better defense, but his injury will keep him down.
3. Dirk Nowitzki - Easily the most slept on player this season. He has been playing above average defense, the Mavericks have been the best team in the league since January 1st, and his stats are on par with anyone in the league.
4. Tracy McGrady - A balance of all the things above. Leading a great team having a great year after a slow start.
5. Kevin Garnett - Having an average year by his own standards, but his own standards are pretty damn high. Garnett's off year is still good enough to put him 5th on my MVP voting list.