Guerilla Union will announce the official lineup for Rock the Bell's 2012 touring rap festival on May 15. The official website hints that one of hip-hop's most influential groups will be reunited. Who will it be? And who will headline this year's premiere rap festival?

The official 2012 'Rock the Bells' launch party takes place on May 15 at the House of blue on Sunset Boulevard in Hollywood, Calif. The festival's official website currently features a clock counting down the days, hours, minutes and seconds until the lineup will be revealed. The page also promises a show that will outshine all previous lineups:

We know you all have been dying for some Rock the Bells leaks, so here's one for you:
One of hip-hop's most influential groups will be reunited at this year's Launch Party!

In order to have all members together for the first time in years,
we have decided to move the Launch Party to Tuesday, May 15th.
Trust us-this group is worth one extra week of anticipation.

In addition to this reunion, the caliber of artists and the magnitude of this announcement
is going to make for the biggest Rock the Bells yet. This is history in the making.

On Twitter Hip-hop fans expressed their excitement and speculated over which classic hip-hop group will reunite this year. In the past influential rap groups including Tribe Called Quest, Wu-Tang Clan (with deceased member ODB's son), De La Soul, Mobb Deep, Public Enemy and the Souls of Mischief have reunited to perform classic albums in their entirety.

I'm fairly certain that the mystery group that will be re-united for Rock The Bells is Outkast, tweeted @Cali_KB .

I have a big feeling that either the fugees or outkast will be the surprise performance at the RTB launch party, guessed @yovana_8 .

Next concert on my list is rock the bells I can't wait till they announce who's coming this year, wrote @ey3s_low .

@stepherz4U : Rock the bells line up announcement is tomorrow! sooo stoked!

@La_Rawr_Uhh : I really hope living legends are on the rtb lineup!

This reporter's dream lineup:

Jurassic 5 performing Quality Control (or Power In Numbers if they prefer, Erykah Badu & Jill Scott Heron, Outkast, A Tribe Called Quest performing Midnight Marauders (yes, again), Kanye West performing College Dropout, Gnarles Barkley performing St. Elsewhere, DJ Danger Mouse and MF Doom performing Danger Doom with all featured artists. Ok, I'll stop there because this has become a complete fantasy, but wait till you hear my ideas for news Rock The Bells stages...