Company are Doing Stuff

I am not a grammar whiz. I will not claim to know all the nuances the English language has to offer. I do not know if the following conjugation of "be" is correct, but I find it grating:

... the possibility of a September release and the fact that Nintendo are already producing final Wii units ...

(via 43things.com)

Nintendo are a company. They make video games. Nintendo are... plural? How did I avoid this usage for so long?