Talking strictly U.S., Britney's album will BOMB. Like 500-600k total sales, which would be a big flop for her.
It's hard to predict Gaga's total sales. It would depend on the next couple of singles, but I imagine a 50% drop in sales for her at the least.
Katy will score another platinum selling album, but not a double platinum. I think more in the line of what Bruno & Pink have been selling (even though those albums will go 2x Platinum eventually).
