I don't think you could do get away with trying to make the ROV Cape plug directly into the Pi. The pins just don't line up and if you look at the schematics the ROV cape is ready to do a bunch of future stuff. I think the best solution is going to be making a "sandwich" using a generic perf board. Second best would be the same scenario using a Beagle Bone Proto. It's all part of the "fun of learning" so until a better solution comes up we will all just keep hacking away at different ideas and expanding the options that can be used for the ROV.
Another problem with attempting to manipulate the Rov cape would be that it can't go back onto a beaglbone after. I still plan to use it on the BeagleBone and I also want to document my trials trying to connect a stock cape (Even if mine is a prototype and not a production) to multiple different units to offer many options. If we completely resolve the R Pi I am looking at a Android device next. :)
Another option along the same idea is to approach connection the cape to the pi by flipping the Cape upside down and using the existing female headers. I am using the male headers from the bottom simply because I want to protect them from shorting. I.E. when I was testing I had a few old shopping cart cards (the plastic credit card bonus tracking type thing?) shoved between each layer for insulation. A proper mounting would need to be arranged for a more permanent use.
Good discussions. Thanks for driving the thought process!