I love interactive whiteboards. Everything that could be done on a chalkboard I can still do (even add the noise of nails on chalk board if I can ever think of a reason for doing so) and SO much more.
As with any piece of technology, people have to learn how to use it fully and some do that faster than others. I can use music, sound effects, visual images, film clips, websites, pictures of the students themselves - the list is endless. There is fantastic software out there that makes all kinds of difficult concepts easier to explore - I can highlight pieces of text, annotate it, zoom in and out, hide some info, run a tickertape message at the top with reminders or hints. And I'm not an expert by any means!
Also, al, the kids can do the same thing. They can manipulate text, crunch it, add their ideas, and I can save the whole thing and print it out for revision notes.
I've never heard of a PTA paying the wages of a member of staff, and clearly if a Senco is needed then that should come first, but I would respectfully suggest that lovely handwriting is not as useful in this century as computer skills, and that there may be other factors in the improved academic performance of children in the private sector rather than just the absence of whiteboards.