The unofficial Fallout wiki has seen traffic spike by 700% following the release of Fallout: New Vegas.
There's a heck of a lot to see and do in New Vegas, and it would seem that players are keen to share their experiences with others. In the week following the release of the game, "The Vault" - the name for the wiki - logged nearly half a million man-hours, or over 54 years of work, in less than a week.
Traffic on the site increased sevenfold, as 2.5 million visitors wrote hundreds of articles about the game's locations, characters, quests, and of course, the many, many bugs. It's believed that a large amount of the information on the wiki has been copied directly from the half-a-million word long New Vegas strategy guide, which is a little sketchy from a moral point of view, but does display some impressive dedication.
Considering that you can sink dozens of hours into New Vegas and still miss things, having a guide to refer to now and then is incredibly useful. It's not quite as convenient as having an actual physical guide you can refer to, especially if you're not playing the PC version, but you can't really complain about something you got for free.