We all know I prefer IRC better. As far as hacking is concerned, usually the brunt there is on the actual IRC servers, which are off our site. So as far as hacking, IRC is much safer for our site. Even when using a Java chat program, if it is IRC based it is still safer.
There are other java clients, I linked Rick to one in PM a while back, maybe that would help out anyone that does not like what we have now.