The change in
alter self appears to only allow 'racial bonuses' and any additional limbs. Any (Ex) abilities, like Darkvision, don't carry over. Still, it has plenty of uses.
"Great, those orcs are guarding the prisoners. Well, I'll cast
alter self and try to bluff my way in so I can untie them & sneak out the back. Good thing I can speak orc..."
or...
"Looks like a tough crowd in there. Let me
alter self into a gnoll and pretend to be your 'pet'. That should impress them..."
and...
"Gah, we'll never find them in this swamp at this rate. Let me
alter self into a minotaur..." (Minotaurs recieve a +4 species bonus to Search, Spot & Listen checks. Too bad they're 6HD... but, add the Scent feat from
Masters of the Wild and you can sniff out your target!)
plus...
"I've gotta hide or those drow will kill me! Can't see where I am in these caves... better
alter self into a troglodyte!" (Trogs recieve a +4 bonus to Hide checks, or a +8 in rocky or subterranean environments.)
So, the bluffing, altering sorcerer has some potential.

And at higher levels, there's the
polymorph spells and various other transmutations for fun. The only drawback is that
alter self is a 2nd level spell, meaning you don't get it until Sorcerer 4. So, your first three levels will be for 'enhancement' spells like
charm person,
change self and the staple spells (
mage armor, attack spells, etc.).