Greatest Hits/Best Ofs

Rihanna in concert, 2011.  She came to Syracuse just months before this show.

I don't usually write about todays Top 40 artists because it's almost too easy (I'll just let Perez Hilton do that), yet there are a number of them as well as some from yesteryear that have yet to release a greatest hits and/or best of album and have enough of a track record now to fill one up.  Russian bootleg ones exist of many of the following, but an official release is imminent for all of these artists:

Rihanna (above; already approaching the tenth anniversary of "Pon de Replay"!)
Beyoncé (Destinys Child have one)
Coldplay (Chris Martin recorded a duet with RiRi which could go on both albums)
Justin Timberlake (there is one for 'NSYNC proper however)
Kate Bush (last one was in 1986, so she has more tracks to collect)
AC/DC (have refused to put one out, yet the end of the band is likely not too far off)
Metallica (also declined to make a compilation and own their masters)
Lady Gaga (just performed with Metallica at Grammys)
Tool (not quite mainstream yet they too don't believe in a collection)
Katy Perry (maybe in 2018 for the 10th anniversary)
Scissor Sisters (overlooked at home and currently on extended sabbatical)
Lana del Rey (yes, even her)
Selena Gomez (includes with the Scene)
Miley Cyrus (not including her Hannah Montana material from more innocent times)*
The All-American Rejects (much of these are on Polydor where I found many of these)
Take That (also underrated in the US yet have enough since their reunion over a decade ago)
The Jonas Brothers (the teenybopper nature of their classics may limit their appeal now)
Yeah Yeah Yeahs (including some solo Karen O)
Mariah Carey (compilation and/or boxed set of her Universal-owned albums)
One Direction (now on hiatus)
Taylor Swift (may have to wait until 2018 as new album is out; her ex is in 1D)
John Mayer (Taylors other ex as well as Katys; Mr-Can't-Make-a-Commitment!  Coming soon to CNY)
Calvin Harris (this isn't a gossip column, yet he also used to be with TayTay!)
System of a Down (a new studio album is needed as well)
Little Mix (even them already)
NERD (could throw in solo Pharrell Williams*)
Justin Bieber (even though "Baby" and "Love Yourself" couldn't be more different; Selenas ex)
Susan Boyle (the time has come for a collection; I do admire her for being a late bloomer nonetheless)
David Gilmour (should keep live versions of Floyd proper classics off so he can stand on his own)
Kanye West (he thinks he's the greatest and may also think that of every track he's recorded.  I'm not endorsing this baciagaloop, just saying how even he might consider putting a collection together)
Alicia Keys (may have to wait until later in the year as Here is still fresh in promotional phase)*
Usher (will also have to wait as his latest release hasn't been out that long either)*
Shakira (this one would be of her English-language hits like "Don't Bother" and "Underneath Your Clothes")*
James Blunt (currently has a studio release to plug, but a compilation next year would mark a decade since "You're Beautiful")
Muse (bought a few of their studio albums for you-know-who but even he can't be bothered with cherry picking)
Fiona Apple (could also use another new album first)
Fantasia (only Idol alum here)

*The Voice judges past and present as this pattern occurred.  No past contestants combined however have enough to do a collection just yet!