10 Things To Know Now: Gaga's New Song, Bieber Sings 'Call Me Maybe' & Jessica Simpson's 'Twins'

Justin Bieber sings 'Call Me Maybe' and more!

1.) Check out a mashup of nearly every mega pop song released over the last year that includes snippets from Katy Perry, Rihanna, One Direction and more. AKA: THE BEST MIX EVER CREATED. (BuzzFeed)

2.) Justin Bieber admits he's still addicted to Carly Rae Jepsen's "Call Me Maybe" during a recent fan Q&A and even sings the tune along with the fans! Anyone else impressed that nobody in that audience actually screamed out a phone number for Justin to call? (Idolator)

3.) This has been the best month EVER for Austin Mahone! First, the YouTube-sensation-turned-hearthrob meets Justin Bieber, then he's treated to throngs of screaming fans in Times Square! (No word on whether New Yorkers got their hearing back yet.) (MTV News)

4.) LL Cool J turned computer geek when he created a software program for music recording and producing. We're kinda wondering if a line of rapper-friendly pocket protectors is also in the works. J/K! (Vibe)

Check out the rest of this week's 10 Things To Know Now after the jump!

5.) Jessica Simpson recently tweeted a pic showing off her, ahem, very large twins... and we're not talking about babies, guys. (PopSugar)

6.) Lady Gaga not only revealed her sexy undergarments while in Melbourne, but she also unveiled a brand-new track, "Princess Die," during her concert in the Australian city. Now that's a G'day! (Sorry, guys). (MTV Newsroom)

7.) Take a moment to watch Drake smoke a hookah while he previews his own new song. (What? You expected to find him sipping chamomile tea and nibbling on crumpets instead?) (RapFix)

8.) No Doubt release another video of them working on a new tunes for their new album, Push And Shove. SPOILER ALERT: There are horns! (Idolator)

9.) We're flipping about Selena Gomez's possible collabos with fun. and Taylor Swift on her next album, but don't expect BF Justin Bieber to take part. We don't blame her -- a girl just needs her "me" time! (MTV News)

10.) We've been swooning uncontrollably while listening to Mika's newest hits, "Make You Happy" and "Celebrate." But we're basically a heap of joy-tears after listening to him discuss his forthcoming LP, The Origin of Love! (Arjan Writes)

Photo credit: Getty Images and Picture Group