They do twit? I will have to check that out, lately I really seem to need it. Maybe I should start using my tripod. What a bother it is though. When I go out it take a bunch of photos in just a few minutes. The tripod really slows things down.
Jacki, here is a great site for comparison pictures. You may have to just keep taking photos for a year to see the changes in each plant.
http://www.succulents.jp/photo...
This site confirms what twit said about Xanthoheuff being bright green through most of it's stages. Hope you have high speed internet, this site can be slow to load because of all the pictures.