Here are the best stories I have found:
Not surprisingly, @Felix Salmon has the best, most referenced analysis: Avis’s Smart Zipcar buy
These others are good too, with some interesting financial info etc..
Did Zipcar investors stay too long>
Roben Chase, Zipcar founder, questions whether ‘old’ can do ‘new’, innovation
A profitable but disappointing exit for venture firms
@OM: Google cars and the inevitability of the internet
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