Wow, has everyone forgotten the tabaxi? They go way back to the 1e Fiend Folio... catfolk have been around in AD&D for quite some time. (I know Mystara predates it, but that didn't have the "A" in front of the D&D until much later.) I have used tabaxi as a pc race for years, and a few years back I introduced the canus, who are- obviously- a race of dogfolk.
In my campaign, both the tabaxi and the canus are from "far away" and don't pop up much in the main region of the campaign. However, a large group of tabaxi migrated there a few years ago at the behest of some pcs.
I like all the weird humanoids; but the key to making them work is keeping them different from the elves and dwarves and humans. Otherwise, why bother to use them at all? And I also think that it gets harder and harder to justify yet another sentient race as the number of them blooms. To fit everything in, you need a really big world.
(Which is one of the reasons my campaign world's so big.)