It looks like they give up versatility for focus in their wildshape, but I can't seem to find where they give up anything else, at all.
One of my friends seems to think they should give up a Thousand Faces like the Dragon Shaman, but I see no such mention of it under the Saurian Shaman archetype.
EDIT: I guess they do give up venom immunity at the very least, but we're only level 6 right now, so that's fairly inconsequential.
under bonus feats : This ability replaces venom immunity.
totemic summons for thousand faces is on http://www.d20pfsrd.com, but I can't find it in the book either.
p.s."function" could be interpreted as "not including what it replaces", but the intention seems clear, good catch Cheapy.
Their totemic summons otherwise acts as teh Dragon Shaman's totemic summons, which replaces Thousand Faces.
...meaning the saurian shaman (and shark shaman's) totemic summons replace Thousand Faces as well.