[Morthoron]

There are two separate issues here: the first, the anthropomorphic speech in The Hobbit, and second, the speech indicative of Valaric servants.

If you divorce yourself from the rampant animal-speak in The Hobbit and concentrate on The Silmarillion and Lord of the Rings, one is left with only two instances of such speech, and both are tied to the Valar: Huan, the hound of Orome, and the eagle progeny of Thorondor, messenger of Manwe.

Yes, eagles speak in The Hobbit as well, but I believe that is merely in accordance with Tolkien's previously written Middle-earth material. The balance of the anthropomorphic speech in The Hobbit, and particularly the birds speaking selectively to the dwarves of Durin's folk or men of the royal line of Girion (like Bard), are just two of many folkloric motifs that Tolkien used, like so mant building blocks, to construct his tale of Faery (or fairytale, if you prefer), The Hobbit.

Motifs like the talking purse, Beorn's animal servants, and even the grumbling wargs ("My grandma, what big teeth you have!"), are borrowed from previous fairytales, not unlike the dwarvish naming conventions lifted from The Voluspa. They do not connect to the divine in the same manner as in Tolkien's more serious efforts. Therefore, Fatty Lumpkin, Bill the pony, or the wargs, do not speak in LOTR.

P.S. As Inzil mentioned, dragons are a separate case altogether and a reptilic representation of greed and malice, but they too were servants of a Vala, Morgoth, and were spawned with fell spirits inhabiting their massive frames. In addition, of course, talking dragons as a folkloric motif are manifold, and Tolkien himself used such a motif in another fairytale, Farmer Giles of Ham, in which the dragon Chrysophylax was the gabby drake.