Let's face it: Coming off a month packed with blockbusters like Spidey 2, Godzilla and X-Men: DoFP, Maleficent will be a tough sell. It will face greater competition than Oz. Jolie and her daughter aren't as intriguing an option as Kristen Stewart and Chirs Hemsworth for lead characters (SWATH). However, the 3D and the Disney marketing will help it barely surpass SWATH domestically. I say $165M.
Overseas, is the same. Sleeping Beauty is more popular than Oz, but competition is too much. However, given it has a two-week window before How to Train Your Dragon 2 is released in some markets and given that it is the summer season (so greater weekday grosses), I think it can make $290M, for a worlwide total of $455M.