Gaga's tour gross will be less than Rihanna's and Katy's and Femme Fatal. The tour won't even make it all the way because her ego won't take it. Her hip will flare up again or she'll enter rehab halfway (Ke$ha her impact)
I can sense that it'll be cancelled, a la Bionic its tour, to save face for underperformance (like when BTW Ball only sold out 50% of its tickets in the US and she had to cancel).
I'm sad we didn't get to see Gaga's reaction when she woke up on August 13th and checked Kworb thinking Applause already sold 2 million in 5 hours and made Katy pull off Roar from itunes or something. It's probably been such a struggle for her these past couple of months. Her ego.