Price. I was in Bow for five years and loved it but my budget stretched to a manky one bed flat in Bow or a two bed house with forty foot garden in E11. No brainer. Maryland is on Crossrail, that's the next big boost for the area.
Antic taking over the Red Lion can't be overstated as a catalyst for gentrification in Leytonstone, suddenly you saw middle class people that you didn't really notice before, people priced out of Stokey and Hackney are moving in. The borough currently has the highest house price inflation rate in the country (28%).
The Olympic Park developments are only just beginning, there's a lot of jobs moving to the area, LBWF has the lowest proportion of residents who work in the borough in London and I can see that changing. I can se the whole demographic changing in the next ten years, in a way it's strange to think that the perfectly lovely late Victorian housing stock is finally returning to being someone's prized home, after decades of stagnation and decay, since the fifties really.