hmm...
i would like to wait and see what WOTC has to say about that...
but, I would be more inclined to go with any non-evil. the last paragraph of the prestige class mentions that most bladedancers spend time hunting evil creatures. i see this as something that mostly non-evil characters would do. the last paragraph also describes bladedancers as being very loners, eccentric, and noisy, which in my opinion, describes many chaotic characters.
in my opinion, i would go with non-evil instead of non-chaotic, since I feel it makes more sense, based on the description of the prestige class.
on the other hand, i am a big advocate of DM's changing things to suit their campaign, so if someone feels that chaotic is more appropriate for their campaign, then go for it.
BTW, at the beginning of the FAQ, it mentions directing any rules questions to
custerv@wizards.com. Is this different than the Sage? I thought that the Sage was still working in that capacity, although he is no longer an employee of WOTC.
that being the case, who determines what is actually eratta rules-wise, the sage or this custserv@wotc, whoever or whomever they may be...