I think SilasX is not suggesting that it isn't a insult, but rather that a word being an insult is not what really matters as far as naming is concerned. What matters, according to him, is whether the word automatically elicits a strong negative emotional reaction. That a lot of words that elicit such a reaction are used as insults is mostly incidental to the argument.
If calling your product RetardedDB or MentallyChallengedDB in a professional setting is OK by his standards because it's not spelled in english, then I'm OK with that. That's what mongo means in spanish, btw.
Okay, there are separate issues going on here; let me try to clarify:
Is "mongo" the equivalent of English "retard", in terms of being a low-class insult that invokes a visceral reaction among the majority of the population?
I didn't believe that at first; if so, why didn't anyone ever put it in Wikipedia? English has "retard" (in the pejorative sense):
If it's merely an insult with numerous other meanings, I don't think it's comparable.
But let's assume it is equivalent to "retard". In that case, I would agree that it shouldn't be used as a name. But you have to pick your battles: all words will have that trait in some language. For my part, I would consider the Spanish-speaking market big enough not to expect them to buy [the equivalent of] RetardDB. So I agree there.
Edit: I agree with the sibling commenter networked's points.
First of all, Wikipedia isn't infallible. Second, genkaos and myself grew up on different sides of the world. Culturally different, and yet, in our own respective cultures we learned, however wrong it is, the implicit meaning of mongo when used derogatively. It doesn't have several meanings as you pointed out, it has one, which does not mean it is the same for genkaos. As you pointed out in the Wikipedia link, it refers to certain type of people. When used as an insult, towards to a, whether the person is white, Hispanic, black, whatever, it is implied that that person is that sort of person and a retard. Thus, my comment of it being racist as well.
Now, even if I had associated MongoDB with that explanation, and now that I do remember it's inherent meaning under a certain context, I take no offense in it since the people behind MongoDB didn't have that intent. Obviously this is an assumption on my part.
Let us not get derailed from the main point, which is the 'visceral' feelings that cockroachDB has on so many people as you mentioned in several comments. It is true, it happens to me as well. But not the word itself, but when I'm around one. Those feelings of fear, whatever, when around one are irrational. I don't remember the explanation why it's irrational, I've never worked in the field of psychology.
And that's my point. You're only offended because it's in english (and that's fair). But no matter what name you use, it will offend someone. CucarachaDB will fly under the radar.
Maybe you have to be culturally immersed to know those things. Mongo, mongol and mongólico are the terms you should research.