If I can get it compatible with IE9, is that a big thing for people here? I don't think it would be too hard, thoughts?
So, yes, I think it would be a big deal. IE8 would be even better. But with IE9 compatibility, at least it would be feasible to start using this when IE8 fades away.
XP users will never get IE9 or IE10, and IE8 can't be supported unfortunately. So I guess Chrome Frame will be necessary to target IE8 users.