The earlier conceptions of the South By Southwest Music Conference had more of a level playing field -- the emphasis was more on connecting breaking bands to industry, and industry to fans. Obviously, that idea has shifted SXSW getting bigger and bigger every year, catering not to just music wayfarers to audiences seeking many of the same trappings of any major music festival.

Hence the headliners -- or "headliners" -- that crop up every year, often directly before the conference takes place.

This year is no exception, with some enormous names gracing stages around Austin, Texas, and even a few more to-be-announced. Bruce Springsteen is keynote speaker, plus he's confirmed that he and his E Street band will be bopping around. Jay-Z is throwing a large-scale concert, but for SXSW Interactive Conference-goers. Jack White will be performing one of his first major public shows as a solo artist, Fiona Apple will be bowing new material and Tenacious D will be re-introducing themselves after a brief hiatus.

Keep checking in to SXSW's site and HitFix throughout the festival: there will undoubtedly be many big, last-minute additions and secret shows galore.

Check out a "headliner" rundown below.

JAY-Z
As previously reported, Jay-Z signed on to help out American Express' new Sync initiative with a free show at Austin City Limits Live tonight (March 12). The show is for Interactive badge holders and AmEx users who managed to jump through a few hoops in order to procure the complimentary stubs. If you can't make it, fear not: the show will be live-streamed online and on a screen in downtown Austin.?
When: Tonight (March 12) 7 p.m. CST

BRUCE SPRINGSTEEN
The Boss is keynote speaker of the fest, to take place at the Convention Center on Thursday. But then he and the E Street Band are schudule to perform at an "intimate" venue in Austin, TBA. Organizers have set up a random lottery drawing in order to determine who gets to attend that show -- I gotta say, too, it does seem to be an effective way to ward of scalpers for this in-demand show. Word has it, too, that Springsteen will be dropping in on some sets for kicks -- nothing's confirmed, of course, but maybe check out Tom Morello or Alejandro Escovedo's sets.
When: Keynote is Thursday (March 15) at noon CST; confirmed show is Thursday evening

FIONA APPLE
The Los Angeles-based singer-songwriter has been fairly absent in recent years, but she has a new completed effort tentatively due in June and will be previewing new songs and performing some of the old stuff. She headlines Pitchfork's showcase, which also features 4AD buzz artist Grimes, Nicolas Jaar, Purity Ring and Charli XCX.
When: Thursday (March 15) 8 p.m. at Central Presbyterian Church

JACK WHITE
The former White Stripes frontman is busily promoting his solo debut "Blunderbuss" and has randomly done some shows from the Third Man Rolling Record Store van. But he's also bringing some Third Man friends along for this ride: actor and musician John C. Reilly (with Tom Brosseau and Lavendar Diamond's Becky Stark), singer-songwriter Karen Elson (who also happens to be White's ex-wife), Pujol, the Black Belles and Lanie Lane will also play the showcase. The Rolling Record Store will also likely host performances, starting mid-week.
When: Third Man showcase on Friday (March 16) at 7:30 p.m. at The Stage on 6th; Rolling Record Store TBA

TENACIOUS D
Jack Black and Kyle Gass are back at it, ?with the promise of new album and concept "Rize of the Fenix" out on May 15. This stop precedes a full spring tour and headliner gigs at fests like Sasquatch. Black is also at SXSW to promote his film "Bernie."
When: Thursday (March 15) at The Haven, time TBA

50 CENT
50 Cent will be tackling his Interscope debut "Get Rich or Die Tryin'" front to back for Eminem's Shady 2.0 night. Yelawolf, Big K.R.I.T., Slaughterhouse and others will also be on hand to round out the all-rap night.
When: Friday (March 16) at Austin Music Hall

SKRILLEX
Biz 3's showcase got all the more eye-popping with the recent first-time Grammy win for Skrillex, who will be sharing a bill with El-P, The Cool Kids, Spank Rock and more. This is the night you've reserved your dance pants for, wah-wah-waaaaaaunnnnngghhhhhh.
When: Friday (March 16) or, um, early Saturday morning, 1 a.m. at 1100 Warehouse

THE SHINS
The band's last album, 2007's "Wincing the Night Away" scored No. 2, so the group might be looking at  No. 1 album with new "Port of Morrow," due at the very edge of SXSW (March 20). They'll be tackling much of the set at a pair of major shows, one being a standalone at Auditorium Shores at Lady Bird Lake, where the Strokes played last year. They also share a marquee with the Gossip
When: Thursday (March 15) at 8 p.m. at Auditorium Shores, and Live from the Lot at the parking lot at 9th and Trinity, and the VEVO lounge at 4th Street & Colorado on Saturday (March 17)

INSANE CLOWN POSSE
No joke. And Jack White might come, too.
When: Saturday (March 17) at 1100 Warehouse at 8 p.m.

NAS
I just want you to consider the coolness of the rapper's stage-share with Sleigh Bells, with Pete Rock and DJ Premier at the VEVO Lounge. Very cool. And he's speakind at the Convention Center on the changes in hip-hop and his epic career.
When: Speaking on Friday (March 16) at 3:30 p.m., Saturday (March 17) at 8:45

SANTIGOLD
Not to be missed. She'll be headlining, in part, Fader Fort, which was legitimized as an official SXSW event just this year. She shares the night with Danny Brown, too, and The-Dream and Kendrick Lamar play The Fort some other days.
When: Wednesday (March 14) at 6:35 p.m. at Fader Fort