Good Question. One more point can be added to the answer.
You can truncate a table that has a foreign key that references itself
See the link to the BOL below
http://msdn.microsoft.com/en-us/library/ms177570.aspx
How to post data/code on a forum to get the best help - Jeff Moden
http://www.sqlservercentral.com/articles/Best+Practices/61537/