Lumia Icon Denim update scheduled for early 2015 | Windows Central
So, according to Joe Belfiore (VP in charge of the Windows Phone division of MS) we WILL be getting Denim for the ICON and it will come with the 8.1+Cyan update.
"Early 2015" - really, I think it's best to interpret this to mean "the first half of 2015" so as not to get your hopes up about it happening before June. It's hard not to expect it earlier, especially since it was recently released for other Windows Phones, but patience is a real virtue here - and the lack of patience will only add to your stress level. 
The good news is that Microsoft has stepped in and said more than once that we WILL be getting these updates for the ICON. My guess is that MS stepped in and joined with Verizon to help Verizon with its certification process and get 8.1 and Cyan out in a more timely manner (heh). So, we can trust that we will eventually get our phones updated, whereas before Verizon had made no official statement about whether or not we would even get it at all. This has really helped me feel better about the whole thing and I thank Joe for giving us the information he can.
