AC,
I have been pondering this idea and following this thread for awhile. Both solid (silica gel cartridge) and liquid (brine solution) systems have been used in commercial applications since the energy crisis of the 70's happened. Apparently, either method is much more efficient than ammonia systems at transferring latent energy loads. Many supermarkets and factories use their inherent waste heat stream as a source of "free" energy to regenerate the dessicant.
Only lately has the residential segment caught on to this process. The big eye-opener to residential architects and energy experts was the University of MD 2007 solar decathlon "leaf" house, cited earlier in the thread. They won the silver medal. Since then, the university has (you guessed it) built another "watershed" house for the competition and won Gold with it in 2011. It is truly a mad science project that works exceptionally well.
http://2011.solarteam.org/design