The US census bureau has lowered its 2050 growth forecast to between 399 and 438 million Americans. Taking the lesser figure to be conservative, that is approximately 43% growth from 280 million Americans in 2000.
Taking San Francisco population of 776,000 in 2000, and increasing it by the national average of 43%, the population of San Francisco should be 1,109,680 in 2050.
I do not see why San Francisco cannot finally come to terms with its place as not just a top 5 US city in importance, but also a global city to be compared with the best of Europe and Asia. This means intense growth and a focus on creating a metropolitan-focused expansion.
(begin rant) The Central Subway is a good start but there needs to be a Geary corridor as well as a complete rethinking of Soma, which should look more like New York's Upper East Side with a mix of tall and short, in order to accomodate office workers that want to walk and bike to work in the new office buildings being built in the Transbay district. Mission street and Folsom need to lead to charge by allowing 10-15+ story buildings to be built. It absolutely amazes me how little business is on these two streets. Where are the flower shops? Bakeries? Normal businesses that aren't furniture stores or nocturnal nightclubs? City hall should hire me look into that issue

(end rant)