we went in May and our mugs are the bright flourscent pink, blue, and yellow...really pretty..
I took the bigger mug and filled it with water...(here at the house) and then emptied it into the smaller ones and there is not much difference in the capacity...just the look ...
They just changed these mugs to the flourscent colors this past Feb, March time frame I believe...
hope this helps..
and they are trying out some new thing ...that you can only fill up the ones that are bought on that visit ...they have a transmitter or something on the bottom and will only fill when it is recognized...