Just adding some info here... I just did a couple of hours of research, on google, W3, SEO sites, and some discussion boards. It seems the general consensus is that while it doesn't hurt to use identical text for alt and title attributes it is redundant EXCEPT for the fact that most browsers use title for the tool tip.
W3 recommends that alt is to describe the image and title is for extra information.
Most are saying alt should describe the img and title should be used like a caption, as in
alt= sail boat on a lake
title= sailing lake Erie
Would be nice if we could "fill out" these tags in zen rather than them using the images name.
David