Scientific American Nanotechnology: This site is an excellent resource for breaking scientific news about nano. Scientific American frequently gets eminent scientists to write features.
The National Nanotechnology Initiative: This overview of the federal government program for nanotechnology links to some good education resources. NNI also sponsors occasional lectures and events.
The Nanotechnology Bulletin: This site contains interviews with movers and shakers in nanotechnology. If you want to hear what experts inside the industry are saying, this is a good resource.
The NanoBusiness Alliance: This site is a good source for those interested in the business and political side of nanotechnology. It is also a good place to find out about events and conferences related to nanotechnology.
Nanotech Now: This site is a portal that links to other good sites about nanotechnology.
NanoelectronicsPlanet: This is another good headline and portal site, although it is liable to mix nano with micro and other semirelated news. It also has a nanotech stock portfolio and associated convention.