Best debut album

Neil Young and Crazy Horse - Everybody knows this is nowhere. (I'm skipping his first solo release which did not include the band, so technically...)

Crosby, Stills, & Nash

Can't really figure out why Boston so popular. Radio pop with handclaps?

@tooblue  A very under-rated album. I wish they made more albums.

Jaco Pastorius' self-titled debut.  Audible sublimation. 

I'll second Pearl Jam's "Ten" - one of the best front-to-back debut albums I've ever heard from a song quality perspective - Hendrix, and may of the other usual suspects.

I would also add:
Norah Jones "Come Away With Me".
Gn'R "Appetite For Destruction". 

My top 3 debut albums
1.  Jim Hendrix Are you Experienced.
2.  Pearl Jam Ten
3.  Guns-n-Roses Appetite for Destruction 

Difficult decision with other debuts such as Led Zeppelin, The Doors and many others.