emss or ROS - which will it be?

There is a class library at SourceForge called emss which was a Senior project geared towards writing a C++ library for use with the iRobot Create. I need to explore this library to see if it has any utility in the robot that I will be making. ROS has so many creative things, as well as a vibrant community of individuals who are contributing to it continually. The only difficulty is that ROS seems to be geared towards big processors and more horsepower than the little ARM processor in my Chumby. I would like to see ROS being used in a good way, perhaps being able to scale up the processing by adding one or more Chumbys to the mix. That is something to think about.