Good article, and definitely worthy of a poll, but....

I would think that retiring without any defeats is not neccasarily a sign of a great boxer....otherwise Audley Harrison could have fought bums in the back alleys of the US for another 5 years and retired undefeated, but got too big for his boots and thought he could be a great, picking some fighters near his level and showing he didn't have the heart.

As for those up there, I think Calzaghe will retire undefeated, but then I'm biased as a massive Calzaghe fan.

Also, IMO, having retired undefeated with a title means one of three things, and I'll put these in what I think is the order of likelihood:

1) He got the belt then ducked the big fights.
2) There was a dearth of talent in the division at the time, and no one could step up with the class to beat him.
3) True great pro.

Personally, I'm torn between whether Calzaghe fits into 2 or 3, and to really test how classy and to be a true great, he'd have to beat one of the recognised top light heavies for a belt, as it looks like Kessler and Bayer aren't going to come off.