Have been wondering about this topic for a couple of days. I think at this moment the so called digitally optimized lens are only a marketing ploy by the lens manufacturers. These lens would not work on cameras with Full Frame sensors, you would have dark edges in the corners since the lens is smaller that the sensor.
Let us look at a scenario when the default sensor size of all Camera bodies are full frame and I think the day is not too far away (probably around 3-5 years). Does that mean all the current so called digitally optimized lens would be unusable in these camera's.
In that case isnt it advisable not to go for these Digital lens and stick with film lenses.