Whilst Reue's analysis is an exaggeration, there is some truth in a strange situation that is developing.
I graduated from the Uni of Leeds, and amongst my friends now one group got graduate jobs in London and are now on their first or second promotion and are earning say £45-£60k, the others that stayed in Leeds generally got non-graduate admin type jobs and are say earning £25-27k.
The difference is it's that second group who have got houses! The first group even on those salaries (apart from a few who had parental help) are basically renting and many still in flatshares in their late 20s and early 30s.
As they've moved up the salary scale the renting arrangements have changed - some of the couples can rent their own small one bed, and the single professionals have moved out of multi-occupancy student type flats and are more looking at living with 1 or 2 other people (often someone in their late 30s/40s who has managed to get a deposit down for a place but needs to take in a flatsharer to cover the mortgage).
But still the core issue is they are renting and are finding it quite hard to save significantly for a deposit because London rents cream so much of their income.
I think it is a reality of modern life - if you are moving down to London for a career, and don't have parental assets and help to call on, the reality is you are likely to be renting in some form for a long time. Saving for a deposit is hard because so much of your salary, even a decent salary, gets sucked away in rent.