My bad I didn't realize vanz went sheik. But still, there's a lot of evidence that peach is moving up as a character.
I'm not saying that only APEX 2012 is to decide what the tiers are. Look at past results.
Genesis 2 top 16: 2 Peaches, 1 Marth*
Genesis 1 top 16: The only Marth was M2K's, and Marth is his secondary. There were 3 Peaches.
Apex 2010 top 16: 2 peaches, 2 Marths and the Peaches placed higher overall (2,9 vs 3,13).
Armada won genesis 2 and Apex 2012. He also got second in Apex 2010 and in Genesis. And in all these major tournaments, the only Marth main to make it to top 8 is Taj, and he did it once (at genesis 2 he got 3rd)
As you can see. Peach is consistently doing better than Marth.
*I'm not including M2K as Marth here because he played mostly sheik at Genesis 2. I saw him play fox more than I saw him play Marth. In fact the only time I saw him play Marth was vs Mango game 1 and he rage quit while Mango still had 4 stocks. He switched to Sheik and almost won.
http://www.youtube.com/watch?v=oXpH6VaTwiE