I use Yahoo finance many times daily, much more often than Google finance or other sites. Yahoo offers real-time update of broad market indices and delayed update of my favorite stocks on their main page, along with headlines and videos of the top business stories. It's a nice information packaging job.
Of course my broker supplies all that data and more, but they don't understand the complexities of corporate firewalls and http tunneling. Not to mention information stovepiping -- you know, one page for news, a separate page for quotes, another page for charts ... Yahoo integrates all that for free.
I used Yahoo finance before the market tanked (No, really before, I got out in time). I loved how easy it was to view up to 100 years of history of almost anything. Certainly helped me believe there was absolutely no reason my modest portfolio would grow much further on the stock market.
I used Google Finance when I needed to check out some stocks (twice a year or so) just because googling "GOOG", "MSFT" or "AAPL" shows a link there. Original article mentions 20M uniques for Yahoo Finance; I looked on Crunchbase for Google Finance figures -- it's mere (in comparison with YF) 1M. Surprising.
Of course my broker supplies all that data and more, but they don't understand the complexities of corporate firewalls and http tunneling. Not to mention information stovepiping -- you know, one page for news, a separate page for quotes, another page for charts ... Yahoo integrates all that for free.