This is what Capcom said:
“Late last year we announced the console-sized adventure that is Resident Evil Revelations would arrive on a 4GB card instead of the standard 2GB card; this increase in memory size led to an increase in price as well, raising the retail cost to $49.99. And while we’re confident in the game’s value at that price (and the reviews reflect that sentiment as well), we’re also exceedingly pleased to say that after weeks of effort, we’ve been able to lower the price to $39.99.
“Since the announcement of the $49.99 price point, we’ve spent weeks looking for a way to bring your cost down to standard 3DS pricing. Today we can finally confirm we were successful in this, and hope the reduced price encourages even more people to check out this strong entry in the Resident Evil canon.”