Love it. I built an eerily similar library in 2012, so I'll submit a pull request once I change my code to match yours.
Two questions: will this be built on top of WPILibJ and replace it later, or is it designed to replace WPILibJ from the start? Is there any C++ component, or is this solely a java library? (I'm fine with either)
Also, it may be wise to contain the platform specific (low level FPGA commands / WPILibJ calls) to a small area of the code, so that ATALibJ can be ported to the 2015 platform more easily.
One last thing: it might be better to put everything under org.first, because
http://first.edu/ isn't related to FRC