If I'm looking at the right period it looks like a 0.5% increase in the upvote percentages at the lower end:
* 1.6% to 2.1% - around a $0.97 upvote (for $0.50 bid) as at today
* 2.1% to 2.6% - around a $1.17 upvote (for $0.50 bid) as at today

but a reduction at the higher end: 
* 4.2% and 5.2% bands to 3.6%  - around a $1.56 upvote (for $0.50 bid) as at today

Possibly also the removal of the randowhalebonus upvote? I was never sure exactly whether this was a permanent thing. 

I think that would make randowhale the best value in the market at the moment, even at the lowest upvote (although I'm still looking at this).