Netbook & Notebook ~ is it time to drop the netbook?

What actually defines a netbook… where is the point it becomes a notebook?  I just came across a great blog written by Eric Ogg over at the CNET blog “Crave” that discusses this topic.  As Eric mentions in the blog:
…Which brings us to Dell announcing its $399 Inspiron 11z. It certainly looks like a Netbook [...]