Of course they will but what has been the timetable. I used to have 2 580EXIIs but hated the menu methods and their wireless system so much tha I sold the one I wasn't using. I admit having one is handy, I got an ETTL cord and use it sometimes with an umbrella for OFC and I lately have been usin it for fill at a few event things but I've never taken it seriously.
I do subscribe to the Strobist and Joe McNally getting their emails because I love lighting and am very impressed by Joes work and Davids explanations of things. But I'm still using strobes or natural light for most everything.
But I think I would be more interested in using speedlights if they had a better system, the actual light from them can be used really well, I just don't like a bunch of other stuff. I think it was Zack Arias who made a wonderful list of changes they could make on the 580EXII that made a lot of sense.
I did put together what I thought was a good 2 light 580EXII location kit with stands, Skyports, set of umbrellas and could get some very nice results but hated the problems with PC connectors stopping to mess with the menu controls that I just never got he hang of when I was trying to concentrate on the person I was photographing. Yes I did manual, ETTL and tried to make it where it was something I felt good about but it never happened.
But I hold hope that maybe the next generation will in part be a result of Zacks suggestions and maybe more improvements designed with input from working photographers even if it has to have a whole set of switches on the back of the flash unit which seems foolish in this day and age but having things like a powerful optical flash sensor and replacing the PC connector as well as a redo on the menu and the goofy ratio system - what the heck? People don't think like that anymore, or did working photographers ever. I worked in ratios a lot in the film industry but in a different way i. e. settin the fill 2 2/3 stops under the key but never 1-4, etc.

