The highest I've got in the last 24 hours is 1.76, one time. All the rest were .4, .32, .24, and .16. Site still says "up to 4 mbtc" so I've got my fingers crossed to get lucky!
( talking about bitvisitor of course. )
I think that certain pages are meant for only certain geographic areas ( based on ip address )...
and so if you don't see any of the higher value ones you probably never will.
I have a feeling you're right, but I hope you're wrong ;-) or that they make a change...last week I was getting 4 mBTC and 1.76 mBTC from Bitvisitor like there was no tomorrow. I guess in a way that's exactly how it was ;[