I forgot, IDPA is making a stab at 3-gun now. They have some tentative rules floating around, and have asked clubs to run some matches under those rules and give feedback for fine tuning of the rules.
So, you may see some IDPA 3-gun matches at IDPA host clubs soon. I'd check with Wildcat (link above) and Hamilton Couty Fish and Game and see if they are planning anything.
So I emailed him yesterday asking if he was going to recognize HM.
No answer yet.