Seán told me about a recent article in this month’s Orion- it’s worth the read.
http://www.orionmagazine.org/index.php/articles/article/7278

College Prof in the UK: Dr. Brown
http://www.docbrown.info/page03/nanochem07.htm

So I guess we need to ask “Dr.” Wikipeida:
http://en.wikipedia.org/wiki/Impact_of_nanotechnology

and the guys at Scientific American:
http://www.scientificamerican.com/topic.cfm?id=nanotechnology