first off, i agree with Skip on how the ergonomics of IRC / Browsers contrast...
...but also factor this..
all the "keyboardy-ness" of IRC notwithstanding, we _do_ still use the mouse, dont we.. how would we like it if a quick swish of the mouse would do the magic! (reminds me of the slick auto-copy-on-highlight feature in linux & mirc - show me one person who doesnt love it
)
for instance half the time i wanna close a window (the other half of times i use Alt+Z) i find myself drawing a quick " L " with the mouse, coz for some reason i'm reminded of the Opera environment ( Mirc & Opera - both apps with the "cool quotient", u c ) ofcourse the window won't close which's really disappointing
so gestures r lightweight and easy to implement (look at Clockwerx's
old post ) and best of all u dont havta point at a small tab/button/menu-item to click.. instead, the entire chat-area can be ur arena
..and u can always turn it off if u dont like it
so what do u think?