Well I'm sure it'll be made for 64-bit versions eventually (assuming mIRC's development continues that long), but seeing as there's no 64-bit version of Windows for the home user yet I think it's a bit premature to be asking for it.
I mean right now, what's the point? What difference do you think there'll be between a 32-bit version of mIRC and a 64-bit one? The 64-bit processors/OSes we're talking about are all capable of running 32-bit code, and they're all far beyond the required capabilities to make mIRC run smoothly so there's no performance issue to solve. Off the top of my head I can't think of any area of mIRC where 64-bit code would bring an obvious advantage.
I'm not saying there shouldn't be a 64-bit version of mIRC. I just don't think it's anywhere near the time for it.
