Well, ignoring the very good reasons I gave about having to live in London for my work and DH's business, and not wanting to leave my family who live here...
I love living in a big city. Birmingham is probably the only city in the UK that also feels big (ish) to me, and even that feels a bit claustrophobic. I love Manchester, cracking place, but its tiny. Its not a big, cosmopolitan city. London is on a par with New York, for me. And if you're a city person, thats important. You get used to that feeling of opportunity and possibility, and as wanky as that may sound, it would be VERY hard to imagine living in a little market town with one high street after that.
I love all the culture, art, history, opportunities to see/do/explore (mentioned above) that London has to offer. I love the parks. I love the markets. I love the shopping areas. I love all the choice. Its never boring.
I love that it is very multicultural. That things stay open late. That transport is fantastic. That if something is happening, something is on, something new is afoot, it happens in or comes to London first.
I'm not going to give all that up for a bigger house or a cheaper lifestyle. It wouldn't be a better lifestyle for me. We could be 'mill-yon-aaaiiiires' (Del Boy voice) if we moved up north, but for what? An easy life? I dont want one!
Is that good enough? 