I seem to have a very different viewpoint to many on this thread.
Let me state first that if there is one thing I love more than Newcastle United, it's the city of Newcastle upon Tyne. The city's heritage matters - even if you think our Listed Buildings and parks don't affect your life, they do....and your children and your children's children. I love my beautiful city and I'll be damned if anyone wants to level Leazes Park (the only central one) or Leazes Terrace....or, for that matter, Grey Street or The High Level Bridge. We've lost too much already (Handyside and Royal Arcades, King Charles House, Corn Exchange, etc). Enough.
I'm 55 and went to my first match in 1972/3. I'd embrace a move from St.James's Park - SO LING AS IT REMAINS IN THE CITY CENTRE.
If the site is still available (and I'm sure it could be), then I believe the Arena site is perfect. A stadium of about 75,000 would be ideal and fit this site snugly.
It could sit spectacularly overlooking The Tyne with landscaped access from the West Quayside and Scotswood Road.
Infrastructure is excellent, being a short walk from Central Station. There is a disused rail viaduct that could be renovated for train/metro/pedestrian use.
There is plenty of brownfield/industrial/tertiary land available immediately westward. Possible training pitches, hospitality and community projects. Affordable homes, too.
Such investment in this area on the edge of the city centre would have enormous economic and social benefits to the inner west of the city. Transformational.
We need to embrace change that is to the enhancement, not detriment, of Newcastle.
I'm not averse to a Gallowgate extension and an improved stadium of, say, 58,000. I just believe that would simply be adequate, conservative, insubstantial. This club can do and be more - it can effect great positive change. I'd like to see the present stadium demolished and incorporated into an extended Leazes Park, while a new state-of-the-art stadium of 75,000 should be built a mile to the west.