In the financial results published for the year ended May 2004 they turned over £1,752 million - It takes a lot of daft people to spend that kind of money.
Same group of companies - different business models. Currys have around 380 stores and their core products tend to be TV's, computers and white goods. Dixons also sell computers, but they tend to major in the photo-hardware market ans smaller electronic devices. It's horses for courses, and it doesn't work too badly - the Dixons group as a whole turned over £6.5 billion for the year.