Welcome to WebmasterWorld Guest from 126.96.36.199
Forum Moderators: ergophobe
As to what the search engines will use, that is always a question worth watching and testing. Right now the alt attribute is what affects ranking, from what I can see, and the title attribute is not used as a signal. And that makes sense, because it is what non-visual browsers and screen readers like JAWS will be "reading" aloud.
"Content is "equivalent" to other content when both fulfill essentially the same function or purpose upon presentation to the user."