Even though I don't play bass and have never attempted to I knows what I like dammit. These are the best that I've heard in my lifetime. As with all top ten lists, this is just my opinion, there are probably bassists out there I've never heard of that are kick ass.
10) Jack Bruce - Cream, Solo - I'm a huge Cream fan and I always thought that Bruce was one of the best that complemented Eric Clapton well.
9) John Taylor - Duran Duran - Very underrated bassist. The dude from Live (can't remember his name) once stated that he hated Rush and would just noodle to Duran Duran all day.
8) John Myung - Dream Theater - Felt obligated to put him on this list. Though he sounds "robotic" at times he is still one hell of a talent.
7) Scott Shiflett - Face To Face - Kind of a stretch to put him on this list but he's damn good. Got to see them live in Chicago back in '01 and was thouroghly impressed. But don't take my word for it, go buy Face To Face's self titled album.
6) Matt Freeman - Rancid, Operation Ivy - This guy has some serious chops as seen here. Was happy to see these guys live a few years back, old punkers never die.
5) Muzz Skillings - Living Colour - Complete sentimental favorite of mine. Was kicked out of the band after Times Up. No idea why. But he was replaced by another awesome bassist in Doug Wimbish.
4) John Paul Jones - Led Zeppelin - Overshadowed by the others in the group but was (well, is) a great talent. I would give my left nut to see them live, even with Jason Bohnam on drums. His bass line in Immigrant Song is fucking fantastic.
3) Geddy Lee - Rush - Yeah, I know, blah, blah blah Rush is great, blah blah.
2) Tony Levin - Peter Gabriel, King Crimson - Just a freak of nature on the bass. The reason why I love Peter Gabriel so much and he single handedly saved Pink Floyd's Momentary Lapse of Reason. Got to see him with Peter Gabriel on the WOMAD tour back in '93.
1) John Entwisle - The Who - Undisputed best bassist in rock. Was actually kind of bummed when he passed. When I first heard him as a kid I really wanted to play bass, then I heard his counterpart Keith Moon and changed my mind. Still just an unbelievable talent. My mom (who listens to nothing but classical) even thought he was great, that's saying something, believe me.
Flea - Red Hot Chili Peppers - Should be on this list but I find RHCP kind of arrogant and annoying, how many farking songs can you write about California?
Mike Rutherford - Genesis
Tina Weymouth - Talking Heads
Stefan Olsdal - Placebo
Jimbo Wallace - Reverend Horton Heat
Ben Shepard - Soundgarden
Sting - The Police - He actually is pretty good
Justin Chancellor - Tool
Chris Square - Yes - Another one that should be on the list, but oh well.