abick: Post a pic that will help with suggestions.

I'm hoping that there are better options for you, but if not, there is a product called GroutRenew. Basically, you paint it over your grout to recolor it (I've used it in the bathroom where our grout wasn't sealed and turned dark to make it light gray again). It is incredibly tedious but works. I learned about it on the blog Young House Love.

Didn't they give you a choice of colors before grouting?

that's what i am thinking. maybe i'll leave it for now and see what happens later. Thanks.

Ha! geoffrey is right! If you still have other floors to grout demand that they talk to you before they choose the color in YOUR house.

Have the tilers dig it out and use a grayish grout like snow white or oyster gray.

Can't dig out the joints are too small, they might chip the tile.

I agree with Geoffrey. No white or light grout looks the same after a few years. Don't worry -- it will blend in time.