Looks interesting; however, PhotoFly
1. requires a license of an Autodesk product (as in not free)
2. license is non-commercial (as in don't use this if you want to use it for something other than play)

Sorry, I just wish that when companies put stuff out there like this for people to try, that they actually allow them to use it. I like Sketchup's model. We'll give you something you can use, but if you want more features you will have to pay.