Time was taken to rework animal companions into a final form, and that appears to be simply to provide access to a variety of animals, provided in Monster Manual Style.
But if there's been one part that's been weak, and has stayed consistently weak, that would be familiars. In fact, the only PFRPG Final stats available for any familiar is the Faerie Dragon familiar, which requires the Improved Familiar feat, but isn't even listed as normally available as an available improved familiar.
Now, I know there's likely a good reason for not providing stats, primarily that being the fact that these buggers have 1/2 wizard hp, and you didn't want to include stat blocks with lacking or conflicting information, and the other fact that I don't think anyone in their right mind is going to put their toad into a combat situation, unless it involves a swarm of somethings that won't kill it.
Paizo should create a self-contained file with the Paizo stamp of approval that lists the stats and abilities of the familiars and improved familiars listed in the PFRPG rulebook, as it should be the one-stop source for a player's character creation needs.
The notable exception I'll allow, of course, would be a comprehensive monster manual for purposes of Wild Shape and Polymorph spells for apparent reasons of content limitation. Even then, some animals are already provided for that purpose.
While the Draconomicon Faerie Dragon and PFRPG Faerie Dragon really only seem to have the same flavor, but no readily recognizable scaling from 3.5 to PFRPG (at least for this monster), I look forward to seeing how the other improved familiars receive treatment. Pseudodragons are currently at a CR 1, so I hope they get at least a slight boost, even though the camouflage ability is currently vastly superior to my familiar's needs, considering how horribly weak familiars still are.
Not that I'm saying they need to be an animal companion, but it would be nice if Smogpuff could handle my less-than-agile adventures with traps while he's hiding in my backpack.
EDIT to add: Of course, if the Beastiary includes plenty of improved familiar options as the Faerie Dragon appears in the Beastiary, this could mitigate the exclusion of this content in the rulebook.
Paizo graciously provided a free PDF called the Bestiary Preview which has exactly what you are looking for.
Paizo graciously provided a free PDF called the Bestiary Preview which has exactly what you are looking for.
Ah! I overlooked it, because I confused it with the bonus beastiary, instead.
However, it's still lacking the improved familiars, but I suppose that is perhaps because they might be providing somewhat tougher improved familiars along the lines of the faerie dragon throughout the beastiary.
Perhaps I can use this as a basis for scaling...
EDIT to add proper thanks for pointing this out.