I know "which" can be plural (which are red?) and can be used in the structure "which of them". But is "who" different? I know "who" can't be plural on its own (I can't say "who are dancing now?") but...

Is it ok to use "who of them"? Who of them is going to come? Who of them are going to come?

I don't know. And this article sure looks confusing, and I bet it's wrong advice. http://en.allexperts.com/q/General-Writing-Grammar-680/2008/9/x-178.htm

Have you tried doing a search for "who of them" in COCA or the BNC, Kooyeen?

"Who of them" is not exactly a frequently used collocation. The BNC has zero results for "who of them". COCA has only a single usage example, and it was not used as a question. That single example was used with the verb "is".
I wouldn't call 'who of them is/are' very good grammar, but you will certainly hear it in informal English. Use which.
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 Yankee's reply was promoted to an answer.
I see. I don't like it much, it doesn't seem that common... so I've always tended to say "who among them is" in any case.
Anyway, thanks.
Yes, it seemed strange to me... that's why I asked. Also because I am forgetting English, I haven't used it much in a couple of weeks. Emotion: crying
And I hadn't seen your reply, Amy. Thanks.
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