I think the shelf life for the "pain" IE has caused, is going to be a lot less than we both realise.
The iterations on developing browsers has gotten tighter and it is very much a thriving ecosystem of innovation. As people start using newer versions of all browsers, "pain" from yesterdays browsers will drop. Looking at the recent deal of Mozilla and Google, even with Chrome demonstrates quite clearly the huge value a good browser has for a companies bottom line.
Im not sure if there is a large deal of code sharing, yet I would imagine any effort to bring an "IE" browser to their mobile platform will have it working quite closely with the proposed "html5" spec. This in turn I think would force updates to the "desktop IE".
