It has magnificant architecture, and enough surrounding countryside to represent every single bit of Britain, from Scotland to Dover. It has more castles than anywhere in Britain, ancient religious sites, and some of the best Roman remains in the country - if history takes your fancy. It has both traditional and modern art museums and a science museum, with an Oriental museum that puts the National Museum's collection to shame just down the road at Durham... if that kind of thing takes your fancy. Served by an international airport and the East Coast mainline with easy access to Scotland and the Lakes. Is close to the sea with some of Britain's longest and finest beaches. It is also not a major terrorist target in the UK, has less stabbings than London, and hence a lot safer than London.
Oh, and the North East produces some of the country's finest football players - Chris Waddle, Gazza, Shearer, Beardsley, Jackie and Bobbie Charlton etc etc.
London on the other hand is just an urban sprawl with limited good architecture. The only thing going for London is the variety of international cuisine and shops - While Newcastle has a good Chinese and Indian community, it is not as large or as various as the number of foreigners living in London.