Sorry to be the Grinch, but no chance of that anytime soon or even midterm.
Because in terms of satisfaction this lens sits at the tippy-top even in its current form. And Canon has a long long list of must-do things before they start to tinker with things that are highly regarded for both quality and value for the price.
As for IS, as I said earlier in a 135L thread, "Why paint the peacock?"
Merry Christmas!
