Right. EVERY movie goes down the second week. Wolverine's second weekend gross was less than half the first week's, but it still made good money. The Avenger's 2nd weekend was just 57% of their first weekend, and they made phenomenal money.
So far they grossed $52M on a film they made for $30M. The film WILL be profitable.
A film costs three times its "production costs" to break even because of marketing costs.