I have no doubt that TF3 will pass the 1 billion mark World-wide.
It has been in the theaters for only two weeks now and it has already made more than $650 million in totals. It will still run at least a month or more in the theaters, so I wouldn't worry about not giving Harry Potter a good fight at the Box Office.
We just gotta put our hopes on the people in the US!!
Come on people!! Go and see Transformers 3 in 3D ASAP!!!!
The proof is right here! Every Potter movie has been beat by Transformers so far in the USA! Are you gonna let that record to be broken now when it matters the most?
Don't ask what your country can do for you, but what you can do for Transformers instead!