With the start of a new tier comes new rankings. All Tier 15 ranks have been frozen, archived, and will no longer update. New ranks for now are setup on just normal kills so take them with a grain of salt. But the results are interesting so far.
Early DPS/HPS reports are looking like not much has changed with healers. However melee DPS are showing a 42% drop in Feral Druid representation for top melee DPS.
For ranged DPS Fire Mages seem to have taken the biggest hit with a 30% drop in the top DPS, while Shadow Priests and Beast Mastery Hunters both have a very large increased presence in top ranged DPS. Looking like Warlocks are going to be kings of this tier though.
Last tier showed us ranged DPS were on average roughly 10% more valuable than melee. As of now it has dropped to around 2%.
Keep in mind these are just normal kills so far, but it will be interesting to see how things turn out with heroics.
Edit: Percentiles should now be working.