The Flixxy website, where I got this footage, contains the following caption:
This film, originally thought to be from 1905 until David Kiehn with the Niles Essanay Silent Film Museum figured out exactly when it was shot. From New York trade papers announcing the film showing to the wet streets from recent heavy rainfall & shadows indicating time of year & actual weather and conditions on historical record, even when the cars were registered (he even knows who owned them and when the plates were issued!). It was filmed only four days before the quake and shipped by train to NY for processing.
And here's what Market Street looks like today, over 99 years later: