Also, while it's not officially official, http://www.gamesas.com/bgsforums/index.php?showtopic=610840&hl= is worth a look if you want to know how the Orcs came to be (or at least how some Orcs believe they came to be).
Muah. I blush.
Though I do not myself support the idea of them being such. I must admit, however, that the Trinimac-being-eaten-and-[censored]-out-myth is very, very uninspiring.
Uninspiring or uninspired? If uninspiring, then yes, sure, I don't think being [censored] out is a particularly glorious note in their history. If uninspired, I'd have to disagree. Comparing it to Tolkien's corrupted elves is disingenuous at best, because in one the nature of the orcs is of cruel and savage oppressors, fit for war and war alone, while in the other it's of a dispossessed and oppressed peoples, whose fortunes were tied to the impugned honour of their hero. When I wrote that story above I had to think about what would make orcs tick. I found the answer wasn't in tribal savagery, but in Albert Camus's absurdism, Sisyphus pushing up a giant ball of [censored] every day, swearing under his breath in the sweat of his brow only to have it roll over him again. Then, for good measure, I included some scatalogical humour from Gargantua and Pantagruel, since their entire outlook was formed at that moment their hero turned into a digested hero, and it would have been remiss not to acknowledge that.
The other option was to go the aboriginal beastfolk route, which holds no mystery or questions. In the Boethiah-Trinimac incident, we at least have questions to be asked, like "how did this happen? why did this happen? If myths are a portrait of a cultural outlook, what does this particular myth say about this people? How has it shaped their perceptions? How does it fit into other metaphysical schemes?"
The comparison with Tolkien is about as accurate as saying that since wood elves live in a forest, they're a boring ripoff. They are; if you don't acknowledge everything else written about them.
But Khajiit really are "beast elves." or Betmer.
And Argonians? They're also betmer.
Mer, like any other word, has its nuances. It means folk, in the sense of "us" but when combined with another word, can mean something "like us". The best comparison is the word "lizardman", which doesn't implicitly mean the creature in question is a man or even holds kinship with man.