You mean they really do an indepth critique of the cakes? Not just the comments.....
I believe you have to be a part of the group that comments on pictures the, Gallery Support group, first.
I see the comments every so often and it says in posted pics that they are members of the group
The group was created by members amongst themselves, which is why they call it a subgroup (i.e. it's not a CC group, meaning, not created nor maintained by Heath+Jackie). You could probably just PM one of them to ask how you can get in on the action 
eta I believe the acronym stands for Critique Subgroup Member...have you had a chance to search for that in the forums? I know sometimes the search feature doesn't really narrow it down well but I know I've seen this question asked and answered before.
Goodness, now I have answered you TWICE with no information 
edited AGAIN to add some help maybe 
http://cakecentral.com/cake-decorating-ftopict-579953-.html
http://cakecentral.com/modules.php?name=Forums&file=viewtopic&t=583819 ->>however the "how to join" link from that thread got lost in last year's database crash. I'd still just PM anyone whom you notice is in the group
ceshell: Thanks for trying! I havn't had a chance to search it yet.
Surely, if I was not so busy reading the "embarrassing" thread then I would have a chance to search for CSM !!!!!
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