He defines success as either/or:
a) significant exit
b) large revenue
c) strong Internet brand
While everybody can probably tweak the definitions, the case studies are good reading.
The recent myspace entry has not only good data on myspace, it's plans, etc, but you will find the exit and who actually made what a nice people of informative writing.
Nisan clearly is spending some serious time on these cases studies. They are well worth your time reading.
The blog is www.startup-review.com
[side note: It's probably a bad thing to turn your laptop over and have multiple screws rattle around and fall out, right? Hmm, that's what I thought.. must be Monday.]