Any electronic device can be sealed against moisture, just like an optical scope is. There are underwater digital cameras. Your consumer grade digital cameras that failed due to environmental conditions simply were not designed to withstand them! As for recoil, it's an issue but not one that can't be overcome. There are cannon rounds with imaging hardware in the nose, after all.
The advantages are obvious.. built in rangefinding, automatic and completely customizable bullet drop compensation, automatic windage correction (assuming you know the wind speed), built in IR sensitivity, customizable data and reticle display, and with the right electronics you could actually keep the image stable under recoil. The shooter might not be able to see the scope image immediately after the shot due to the scope moving around, but he could replay the video captured in the seconds after to see the hit.
These are all features many of us would like to see, but not many of use would pay the price it is going to take to make them a reality (at least in the civilian market). I suspect we'll see this in military applications first, and the price tag will be pretty impressive. As was previously noted, there will still be quality optics involved, but the electronics can make up for some of the optical requirements.
In short -- I'm sure we'll see these become fairly common during my lifetime. Just not in the next few years.