forehead,
I teach in a school where a lot of the children have very little in the way of 'life experiences': some have never been to the nearest city (10 miles away), others not seen the sea / been to a castle / been inside a theatre / been to a zoo / been to a museum / met a person of another colour / heard a native speaker of another language etc etc.
Obviously, we try to redress at least some of these through visits and trips BUT with an IWB it is possible to bring some of those experiences a little closer to the children than would be possible using just a blackboard or a book.
In other schools, it might well be possible to say 'Imagine you are at the seaside - what descriptive words might you think of' (or whatever...what a boring task... but you know what I mean) and know that the children in the class have an actual memory or experience to draw on for their ideas.
Like raven, I also find my IWB extremely useful to be able to 'flip back' to saved ideas or material from a previous lesson 'You remember we found out everything we already know about magnets and wrote them on the board and x asked this question here? Today we're going to use that as a starting point...' etc
An IWB doesn't make a good teacher - and certainly doesn't make a bad teacher into a good one. It is, entirely separately, a sometimes useful, stimulating and engaging tool. 'Chalk and talk' CAN (doesn't necessarily) lead to a style of didactic teaching which sees passive children as 'vessels to be filled with facts' (so can bad use of enless IWB presentation files). Interactive tools can (don't necessarily) allow children to be more active - and that may help some (not all) children to learn more. Me, as a child, I loved 'chalk and talk', nothing better. But equally I have seen how more interactive, partipative, active teaching and learning (NB not just interactive gizmos) help some children to learn more quickly and retain more of what they have learned.