If you were a _new_ developer from another platform, what's the first impression you would have of the Playbook App World? Does that strike you as a place you want to do business in? Especially if your other platform is iOS, then the cringe factor will be especially strong.
In market research, how well do you think their product will be represented when it's lumped in with what's there now. Lost in a pile of crap is the first image that comes to my mind. I'm finding CB of a lot more use when trying to find useful apps, than scrolling or search thru App World.
I actually do work for a developer - we have a BB app, but it's a vertical market app that ties to an ERP system, so we bypass the App World. We could have put out a Playbook app, but it was promised that BB apps would run on the Playbook, so there was no need to port. Months later, when nothing happens, the issue just died on the vine. We get more requests for iOS now.