I imagine it certainly will fluctuate from time to time. There will be weeks where the numbers reverse and the Whales power grows. However, as an overall trend, when looked at over a 90 day period, I feel certain it is a trend that will continue as more people join this blockchain. Simply put, they cannot post enough to maintain their position. The reward pool is going to be eaten up by newer people...
Which is great because it will kick off the network effect.