I think it's a tipping point of some sort. Both parties have had to take some pretty populist stances in the coalition-era, and while their approaches are different they are gradually eroding London's attractiveness to the point where it won't be a given for a hot investor to be in the City.
When I moved to UK in 2008 the City was The Shit. Even with Lehman Bros and the world economy collapsing. There was no question as to where you'd want to run your investments from. Fast forward seven years, and being in London has slipped from 'the option' to 'an option'.
NYC, Valley and Hong Kong have now the sex appeal City once enjoyed.
My personal interpretation only of course.
I think that is more due to the increased regulation, fines and such... companies are shit scared at the moment. Maybe rightly so, but because the guidelines change fairly quickly and there is a UK and EU level of regulation it becomes a bit of a crapshoot for the banks. They start to panic and think maybe tomorrow they'll get a billion pound fine for a new rule they weren't quite aware of. So not so much that there is regulation but that it seems to change and the enforcement of them is pretty wishy washy. The FCA as an example can decide to turn up one day and basically demand a full audit. Didn't dot an i and they basically set up camp in your office and you're creating a lot of work and uncertainty. That costs a lot of money and with the recession some companies are skating on ice despite their size.
The costs of moving is huge however so some of it is bluster, some of it is thinking they can make more money in the long run by moving. HSBC as an example are mostly based in asia anyway so it was always on the cards with them.
In any case, the idea that borrowing huge amounts during a golden period assuming it will go on forever like Labour did is just ridiculous. Tories at the time believed it too, but their natural instincts are to save and cut so a lot of their comments are I think a case of "me too" while Labour were in power.
nib95 - You're getting what you wanted for the same problem you mention, London is too costly so a lot of financial business is moving elsewhere. The likes of Birmingham for example. It would help if some of those cities had an airport the likes of heathrow I think, often international business has to come to London first and then travel by train (which are shit) or car (with crowded roads). Catch 22 though, you can build it in the hope it creates that growth but might not happen... yet can't happen without that expansion.
When saying the country should be more than London I assume you mean financial services, in which case what other areas do you think Britain can compete on the world stage?