More revenue? It's not clear how the $10K promise works (the official site[0] doesn't have the T&C populated yet[1]), but there's surely some time within which you must earn between $1k and $10k. After that time, I'd guess that more purchases would still be yours. But it's unclear until the official rules and conditions are posted.
Actually, it looks like RIM is offering to pay the difference between what your app earns and $10,000. So if you earn $4,000, they'd pay you $6,000.
So if your app is not going to go past $10,000, there's literally no incentive to promote it beyond $1,000 (except the enjoyment of knowing so many people are using your app).
It's not clear what the cutoff date is, although presumably it's the Blackberry 10 launch. So to maximize profit, you should promote it enough to earn $1,000 just prior to launch, take your $9,000, then promote it further.
Keep in mind these numbers are over a 12 month period. And according to the fine print, it's a 12 month period of RIM's choosing. If you only sell $1,000 worth over the course of the first 12 months after the launch of BB10, and RIM decides to hold out for another month, and you sell $6,000 worth in month 13, they might just cut you a check for $3,000 or decide to wait another month and see how you do.
IMO, It's not free money though I think it's meant to sound like free money.
[0] https://developer.blackberry.com/builtforblackberry/commitme...
[1] https://developer.blackberry.com/builtforblackberry/document...