With a nitpick (it’s trademark law, not copyright law), I agree with **Suburban Plankton{/b]. It’s not the s on the end that the Lego people need to worry about: it’s the generic use of the word “lego” to describe other building blocks that’s the worry. While I’d use “Lego”, not “Legos”, to describe a pile of Lego bricks, I don’t see that it endangers their trademark, any more than asking for “two Cokes” endangers Coca Cola’s (unless when you ask for “two cokes” you are actually asking for two carbonated beverages marketed by another firm – that’s the problem that “coke” has, and it’s not caused by the s on the end).
The only reason the “S” in “Legos” matters is because it is easier to prove that it’s being used as a generic term - as a noun.
Realizing that Wikipedia isn’t hard and fast as a cite, I’m confident in this entry on trademark genericization, as it matches everything I’ve learned on the matter:
I say Lego, you say LegoS, let’s call the whole thing off. 
btw - did someone refer to “Legos” as being almost a misspelt African capital? Well, no, Lagos is not the capital of Nigeria - Abuja is.
I have a feeling that the twitchiness of the Lego manufacturer is related to previous legal ups and downs; as I understand it (i.e. no cite) when the patents on the lego block designs expired (opening the way for other companies to make compatible systems), lego tried to register the shape of the standard Lego blocks as a trademark; they failed, because the shape was primarily functional, or something like that.
Watch this movie… Revenge of the Brick. Its pretty good.
Well, obviously they don’t care much outside of America, most people outside of America don’t call the blocks “legos”. They definitely do care though hence the direct request NOT to call the them “legos” on this website.
Well, all kinds of brand names have become generic words, despite the best efforts of the companies involved.
In all seriousness, if a guy named Joe McDonald tries to open a restaurant called McDonald’s, he’s likely to face some legal issues, even though it’s his own name!
And Coca-Cola has been fighting a losing battle over this for years. When I lived in New York,m “Coke” meant any cola drink, while here in Texas, “Coke” means any soft drink at all.
Many a Southern comedian has related a conversation like this…
Waitress: What’ll you have to drink?
Customer: A Coke.
Waitress: What kind?
Customer: Dr. Pepper.
Same here. I once got really stupid and typed up a post about spelling conventions. You know, honor/honour, color/colour, saber/sabre, theater/theatre, etc. Why not spell them the way they’re pronounced?
Then I realized that that would make me the kind of idiot who thinks English is a phonetic language, so I laughed at myself and backed away from it.