You've likely noticed that more rentals are being handled by brokers these days, as this is not a new trend. As the NYT reports today, often late to the game as they are, "the days of the Mrs. Madrigals are being replaced with a new reality," and to some extent this has to do with the tenant rights culture around town which has left landlords freaked out that they'll never be able to evict a bad tenant. Brokers, you see, promise landlords they can help them navigate this and offer screening services for tenants.
But then there's the issue of broker fees, which for now are mostly being paid by landlords (but likely being passed on through higher rents). The trend toward brokers signals a shift that could take us more in the direction of New York, where brokers have "a stranglehold" on the rental market and are able to charge the fees to tenants relatively huge sums that could be equivalent to up to two months rent. This would not be the first trend that folks like to put under the umbrella of 'the Manhattanization of San Francisco,' but we hope we at least get a few more tall buildings in the bargain.