|This reminds me of some other game... wait, don't tell me...|
The data have convinced them that straight pricing is the inferior business model. (Though they call 99 cents premium pricing, which sure doesn't sound premium to me.) They plan all their future titles for a freemium business model. They do understand, though, that the design of the game has to incorporate that idea from the start in order to be really successful. The game balance becomes critical between paid and unpaid players; you can't make it feel like the only way to succeed is to buy your way to success.