WFLDWFLD was once the flagship station of Field Broadcasting, which owned WKBD Detroit, KBHK in San Francisco, WKBS in Philadelphia, and WLVI in Boston, all using the same type of look (seen on the WKBD page.) When Field was broken up after the founders had a very bad feud, WFLD was sold to Metromedia. Metromedia sold its stations to Rupert Murdoch, which used them to found the Fox network. WFLD was one of the first Fox stations.
Like WTXF did, WFLD chooses to identify as "Fox Chicago." News is "Fox News Chicago", though most graphics just say Fox Chicago or Fox. Their news is fronted by Walter Jacobson, who is one of Chicago's news legends. Thus, it has a far less hypey tone than many Fox stations, although it's arguably flashier than the other stations in town.
Fox News at 92001
Many stations are required to id their calls at the top of the hour - most put them in the news opens and bury them in small fonts. WFLD, on the other hand...
Theme tune is "Streaming News" from VU Music. 
Fox News at 92004
WFLD changed its open in February 2004. Brighter colours and cooler effects, but the theme is the same, and the rotating call letters stay..