There are so many tools, Web2.0, mobile apps, desktop applications, that the offer so many opportunities for teachers and learners. They offer novel ways to learn, authentic ways to leave, collaborative ways to learn. It is an amazing choice, probably more than ever before. Having just some from a demonstration of the new HP Sprout (not a small green vegetable), it is clear that there's even more on the way. Teachers are faced with a tremendous amount of choice. It can be incredibly confusing. Talking to a maths teacher recently, he was confused as to whether he should use voting pads or Socrative, or some other voting tool a colleague had recommended.
However, the main point to remember is that whatever choice you make it should be based on pedagogy, not novelty, not wow factor. Technology is not at the centre, learning is. We need to avoid technological determinism: I have this tool, what can I do with it? It should be: My learners need to be able to ... What tool would help my learners the best?