I know nothing, other than everyone says that both Christmas Moss and Java Moss are nearly impossible to go wrong with.
That being said, I personally have gone horribly wrong with Java Moss. I suppose part of me takes a certain pride in the fact that I've managed to kill that which is supposed to be unkillable. Mostly though, I'm filled with the sense that I'm a disappointment to myself and everyone who's ever loved me.
BUT, in an effort to overcome that horrible aquascaping setback, I've recently secured some Christmas Moss! This time, things are going to be different!
My best theory at the moment as to why the Java Moss experience went to terribly, terribly wrong is that the temperature in my tank was probably a wee bit too high (79-80 F or so. Oops). Research subsequent to the events in question is telling me that while most moss varieties can tolerate warmer temps, they really prefer it a little on the cooler end of the tropical spectrum.
Any of the pro's here care to confirm or deny?