Huge musical quartets of the 2000s?

In the nonfiction book I'm finishing now, I have a caption showing the Mills Brothers who were a mega-selling quartet in the 1930s to '40s.

I'm trying to draw a comparison between more modern quartets and the Mills Brothers to help the reader identify with the style of this group. Singing and or singing and dancing, it doesn't matter. (Although, I don't think the Mills Brothers did choreographed dancing.)

For instance:

Backstreet Boys of the 1990s.

New Kids on the Block of the 1980s.


What about the 2000s? The "boy band" phase has finally come to pass, but are there any more "hot" quartets in the 2000s? All I can think of is the Jonas Brothers, but they're more of a "guitar trio" than vocal quartet, unless I'm way off base.

Callalilly,

Thanks for the suggestions, but I actually meant currently charted groups. The Manhattan Transfer, from what I know about them, has been around for a long time. And I thought you made up the Anonymous 4 until I googled them and found out it's a real quartet.

So, along the lines of the Jonas Brothers, are there any newer, charted quartets?

And does the Jonas Brothers even fit into my category?

No, I'm not that strict with the term "four-part harmony" quartet.

So, yes, I do mean "pop-music" phenonemon, but not necessarily boy band.

I was thinking, in looser terms, a group made up of four (or so) members, who sings more or less in harmony, who appeals to a younger crowd.

Back in their early days, the Mills Brothers did all those things. I'm trying to identify a modern music group (that everyone's heard of) that is kind of like the Mills Brothers.