With the photographic features in mind and the photo repair angle in our heads is it really worth it?
There are a few features that have been added that might aid us photographers aiming to do photo repairs. Notably the first is the graphic acceleration of some operations. However reading deeper into the blurb and some reputable reviews, the graphics acceleration is not actually going to help us, photographers, very much. The rotation and zoom controls are accelerated by your graphics card but not the filters. The only way these will speed up is with a faster processor and even then I am not sure this helps that much. As for us photo repairmen use the filters quite a lot for selections and making etc then this is of little use.
Another feature that has been added is something called content aware scaling. This enables an image to be stretched or shrunk without altering the content of the image and maintain the content in proportion by removing data that is not needed. I have included an example of a BMW car that I squashed. Notice the wheels are still around and most of the features of the car still look normal. This feature can be used for making wider format images quite successfully especially if you want to stretch a landscape. However, this is not worth the upgrade particularly when you can find this tool, “Resizor” elsewhere on the net and free. You may have to resourceful in your search but it is there. This feature could also be used to fit an old photo to a more conventionally proportioned modern-day paper size.

The content aware scale used to reduce and squash a car
So what else if there to offer? The last feature that I noted was colour range selection by local clusters. It is a fancy way to select colours with a similar colour range within a specific area. The zone of the area can be controlled. Once again this is something you can quite happily do with a circular faded mask and then select your colour range within that area.
Overall then is worth the upgrade? In short, no, not if you are just performing photo repair like me. Don’t waste your money and stick with CS2 orCS3