And now a word from Evangelist number 2...
It didn't take me long to figure out that this will be one very useful tool for my campaign. No need to slave over creation of countless types of alien flora and fauna for me, no sir. One click and I've got a new one ready to go. The PDF is also a nice reference for creature abilities, and I really like the breakdown for methods of classification. It's an easy way to get an idea for what type of creature you're dealing with, in just a couple of words.
Mechanically, I did find one problem with the spreadsheet. For some creatures that have a large number of racial bonuses to skills, there isn't enough room in the display area to see them all. It's a simple enough fix, but with the sheet protected with a password, that falls on the creators.
Otherwise, the only other negative that I can find is that you really need to go into this tool with an open mind and no preconceptions. Some of the creatures generated will make people scratch their heads and say "how can an amorphous plant have a charge attack?" But you have to think of the classifications in broader terms. Not all plants are rooted to the ground, and there can certainly be a vicious quadriped that has more plantlike qualities than animal qualities. Once you get past that (if you even have to), this is a great tool for my own uses, and I'm sure many other GM's will agree.
We now return you to your thread, already in progress...