I WOULD have the ability to create such an app... A few issues though, one big one being that I dont have a Brammo yet. Another big issue is getting the data to the phone wirelessly, which would involve custom hardware, like that mentioned in the article. That piece is simply beyond my abilities.
Now if Brammo can provide the wireless interface, perhaps as an option... (Is Brammo listening?) there would be nothing stopping me from creating an app. But now we are talking about another wireless data bill, which I imagine is a non-issue to someone who can afford a Tesla.
Best option for getting data from the bike (in my opinion) would be to have built in 802.11, but then the bike has to be within range of your home's wireless access point. At least then you could get data to your phone while you are at home, which would be quite useful still.