Does FB London have enough scope?

Facebook seems to be expanding at a breakneck pace in London. Atleast 8 people I personally know have just joined or are going to join within a quarter. I see lots of other people joining as well, from LinkedIn status updates. And this is just from India. They also hire from whole of Europe, Middle East, rest of Asia.
Do they have enough scope for all E4s and E5s to grow?
Wondering if it's worth joining