Having photos in your genealogy is great I would say even essential. But what is the best way to keep them up to date and how should you update them? The good news is that genealogy is a history subject rather than an missing person search(even thought it can be that at times too). By this I mean that you are not handing out these photos for identification but a representation of what the people looked like at a point in time.
Importance of updated pictures
Updated pictures are important if your are going to a reunion and want to know who you will be seeing. If all your photos are from the 1970's you will be assured that you will not be able to identify anyone. The baby is now 35 years old. So having updated images can be helpful in this purpose.
Getting updated photo
The best way to get updated photos is a "take it when you see them" mentality. It may behoove you to start to bring a digital camera to function and trying to get a mug shot of everyone to connect to their profile in your genealogy. Some functions such as family reunions lend themselves to this more than others (i.e.funerals). Also scanning in pictures from Christmas cards is a way to update photos as well Anytime you see the person or a picture of a person that is more recent than the one you have you should find a way to capture it.
The fact is that over a lifetime people are constantly changing. So having the best photo of person attached to them in your genealogy is important. How do you want to remember them? Just because a person died at 80 does not mean that you have to have a photo of them at 79 as the primary picture of them in the genealogy. Having a picture of them as young and vibrant may better suit your purposes of telling the story of their life.