I was always amazed by Geoff Tate of Queensryche.

I guess my choice would be between the following three males -

Roy Orbison
Otis Redding
Elvis Costello

Maynard James Keenan
Mike Patton
Layne Staley
Robert Plant
Freddy Mercury
Chris Cornell

Stevie Nicks
Mariah Carey
Celine Deon (I cant stand her, but she has monster pipes)

I would probably agree with the choice of Linda Ronstadt. If you saw her voice on an oscilloscope as I have you would be amazed at how perfect it is.

Thats a great pick.

Although his voice wouldn't be voted best by most, my personal favorite is Martin Gore.

a few of mine,

freddie mercury (the best)
roberta flack
trisha yearwood
mariah carry
whitney houston
marvin gaye
jackie wilson
sam cooke
barry white
al green
tony bennet
dean martin
frank sinatra

Anyone from THE BAND, especially Rick Danko...soulful as hell!

Olivia Newton-John
Tori Amos
Trisha Yearwood
Josh Groban

I like Michael Stipe's voice (R.E.M.), but I hope he gives up smoking...his voice sounds a little more gravelly every album. :(

Freddie Mercury
Bryan Ferry
David Bowie
Bjork
Maria Callas
John Lennon
Mike Patton

And the single greatest vocalist ever?

Yamatsuka Eye.

Good Call.

Johnny Cash is amazing.

Bono has the best voice in Rock right now.

Sting
Elvis Costello
Annie Lennox
Stevie Nicks

But my picks are influenced by how much I like their music too.

I like ethereal, sad, kind of voices instead of really powerful voices, so I'll go:

Margo Timmins (Cowboy Junkies, esp. "Trinity Session" era)
Emmylou Harris (her later stuff, starting with "Wrecking Ball")

Don't get me wrong, I love Aretha and Sam Cooke as much as anyone else, and Johnny Cash rocks, but those two voices above move me like no one else.

Chrissie Hynde always slays me.

That's who I was thinking of. Sad that we won't hear any more. :(

I would also add:
"Recent"
Shawn Colvin
Bryan Ferry



"oldies"
Sinatra
Billie Holliday
Aretha
Johnny Cash
Paul/John

John Lennon, Paul McCartney, and Brian Wilson are favorites of mine, but since they've already been mentioned, I'll name a couple more that haven't been said:

Van Morrison
Jeff Tweedy
Michael Hutchence
Richard Ashcroft

I can't believe I'm the first to mention.....

Allison Krauss

Easy call for me:

Midge Ure
Morten Harket (a-ha)

I really like John Lennon's voice, but that's already been mentioned along with many others. Also, Liam Gallagher's voice in his early days was great.

My favorite female voice that hasn't been mentioned yet is that of Beth Orton. Another that I don't think has been mentioned is Andrea Corr.

Kirsty MacColl had a gorgeous voice!

You picked my fave right there.

Steve Perry.

my favs

dudes

maynard james keenan (APC/Tool)
lajon witherspoon (Sevendust)
james hetfield (Metallica)
layne staley (Alice in Chains)
johnny cash
eddie vedder (Pearl Jam)
chris cornell (Soundgarden/Audioslave)

chicks

skin (Skunk Anansie)
norah jones
amy lee (Evanescence)
bonnie raitt
christina aguilera

Anita Baker
Chris Cornell
Luther Vandross
Sting
Sade
Brian Mckight
Tupac Shakur
Maynard Keenen
Ronald Eisley
Kurt Cobain
Al Green
Lauryn Hill
Gregory Hines (underrated voice)
Those are my faves