If we were talking about how a cat species lost its hair I would venture a guess that many creationists wouldn't argue (as long as the cat was still placed in the cat "kind"
I agree, so much of this post will be a touch of preaching to the choir. It would be interesting to see the differences between two cat species listed and compared to the list of chimp/human differences.
There seems to be an invisible barrier errected by a lot of creationists between the other apes and humans. To me, the differences are really not too large to be explained by (relatively) small genetic changes and plausible selective pressures.
The title of this thread seems to demonstrate this quite well:
Why on earth is lack of thick hair a major stumbling block?
Likewise, why do upright walking and brain size pose a problem? The only thing I can think of is that
they don't want to think that we are that similar: a touch of the "Urrghhh, horrible hairy ape!". If you look closely at our ape cousins, you see how truly closely related we are.