What Gez said.
I'd go as far as giving them the same amount of bonus feats wizards get. I don't think that sorcerers' spellcasting is so much better than wizards' that they need feats to make up for it.
As I think that sorcerers come in two flavours - the ones that learn their spells intuitively, and the ones that mimic other spellcasters - I'd give them a choice of eschew materials and skill focus (spellcraft) at 1st level, and metamagic (though no item creation) later, and maybe feats like extra slot.