Why corporations choose Delaware [PDF]:

http://corp.delaware.gov/whycorporations_web.pdf

Corporations choose Delaware because the lawyers who incorporate them (usually contracted from big firms) choose Delaware.

If you're really thinking about incorporating in Delaware then you might want to check out this post, "Why incorporating my startup was my worst mistake" http://news.ycombinator.com/item?id=2399139

It's about the experience another HN user had incorporating his startup in Delaware and also generated a nice discussion about things to think about before you decide to incorporate (and specifically in Delaware).

See http://en.wikipedia.org/wiki/Corporate_haven#North_America and http://en.wikipedia.org/wiki/Delaware_General_Corporation_La...

Check these detailed answers on Quora, http://www.quora.com/Why-do-a-lot-of-public-companies-incorp...