For those researching low-cost methods to generate Bluetooth keyboard signals, Adafruit has a $20 module that does this. It runs stand-alone, where you can just wire up switches to 12 pins and have it send preset keyboard commands, or you can hook it to a controller like an Arduino and send whatever you want (such as iCade commands).
The challenge is hooking it up. You have to solder in the pin connectors (bad for those of us who specialize in software, but not so much on hardware), and once you have that, there's still no easy way to hook it to an Arduino project. It's great for breadboarding, though, which is what I will be doing initially.
If I get the project working, I will have a custom shield made that this module can just plug in to so others can work with it without needing to wire things up.