Reliability of U2gigs.com 

I know that there's been discussion of the reliability of U2gigs.com, but I just came across 2 print sources where the site is referenced.  The first is the 2009 book U2: A Musical Biography.  I don't have a copy of the book but a search at Google Books shows that the site is mentioned in the book.  The second is at the very bottom of the page in a 2007 issue of Billboard in a brief article about the songs played on the Vertigo Tour (link).  It's cited as u2-vertigo-tour.com (which, as your probably know, is the old url of U2gigs.com and typing it in will redirect you to the new site).  I actually just referenced this article from Billboard for the "Streets" article, but it seems pretty redundant since I might have well have cited the website directly. Elevation-tour.com is cited in the book U2 Live: A Concert Documentary, and according to U2gigs' FAQ, Elevation-tour.com uses their database.  Let me know your thoughts. –