If overlayed with other non-Texas parts of the country, that's pretty friggen huge.
Here's to the Texans in harm's way. I really hope this is over soon. Good Luck.
Source -> http://www.theatlantic.com/technology/archive/2011/09/the-area-of-the-texas-wildfires-versus-americas-10-biggest-us-cities/244706/#slide10
Related links (with realtime updates on fires, videos and pics) -> http://www.esri.com/services/disaster-response/wildlandfire/latest-news-map.html