People are getting a little nuts and a bit irresponsible about trying to out aliases these days.
I've been helping a n00b through the mentor program. He made a n00b mistake and inadvertantly released somebody when he meant to waive him. Another owner jumped all over him, accused him of being an alias and in general has been making his life miserable this week.
The n00b came back to me and asked WTF was going on? I explained the alias problem to him (he had no clue), how it can be used for cheating, and that some people can be very touchy about it. Justifiably so, if it's a legitimate concern. From what I read in the WC in the world in question, there really was no basis for it. The vet jumped all over a comment the n00b made about the "value" of the player in question, saying that there's no way a n00b would understand or talk about value. Wouldn't let up. My advice to him was if the problem persists to look for a new world to play in.
FYI . . . this was in a public world. But still, if you're going to start throwing alias accusations around, have at least the slightest bit of proof before you do it.