The term "gentrification" was coined in 1964 by a left-wing British sociologist named Ruth Glass. She used the word to refer to what was then taking place in a part of London called Islington. Islington originated as an affluent place, but had become a rough, working-class area. In the sixties, it experienced gentrification. (Actually, it had been experiencing something like it for some years, at least since George Orwell wrote about it after moving to the neighborhood in the forties.) It's where Tony and Cherie Blair and their family lived before moving to 10 Downing Street. (Cherie is said by the London papers to be truly upset that when Tony was elected and they sold their Islington house they got £750,000 for it, while now it is worth £1.5 million.)
Lots of references to Brooklyn, Reason, Jane Jacobs ("Truly, she must be the only writer championed by both Reason and Tikkun"), and more. Whole thing here.