Well, I have been playing for about five hours now xD And I jsut have to say it is great. All these are relaly jsuy my opinions..but..
It never gets old, if your bourd you can jsut do whatever you would like. Im only on the "Tribe stage" wich is the third one. The first stage is really boring, your an aquitic organsim, but its over quick, the second one you are in first person and a primitive creature. Then in that stage you move with your species and fight other species or ally with them. Then once you have enough "DNA" and you have the biggest brain youc ang et, you go into Tribe Stage, wich is then turned into a third person game, you are the Cheiften of your tribe and you know have fire and tools, and you command your people. You don't directly fight. You can gather fish, or kill primitive creatures, which was you in the last stage, and gather their meat for food.
I am only on the third level as I said, so im not a hundred percent sure on this, but, in between 2-3 your going to want to take off all the things you put on your creature, unless you like the other features, like, spit glands to enable you to use spit attack in 2, or a tail, or other things that help you in stage 2, because they do absolutely nothing in stage 3, you sue weapons and clothes there. I regret not doing it because now my people have weird creature things on them along with clothes xD But thats personal opinion.
Oh, and make sure you keep the hands, feet, eyes and mouth if you do decide tot take everything else off.
I do agree with you Mad_Fred, it is very well thought out, and I think the leading cause of it seeming childish, is the graphics, which do look childish, but overall it is really fun. And I do agree it is unique, as, someone else's creature you don't even know could be plopped into your game, and how it goes from first person to third, and so on.
Also, if anyone does play, sometimes during loading screen or other screens it will show some pictures of peoples creations with a little thumbnail, there username and the creatures name, if you see a user named Kona1988, tell me
Cuz, its me.