Emmy Huang, product manager for Flash Player, has posted a blog entry that details the number of daily downloads and installs of Flash Player. As expected, the numbers are really, really big. "In July 2008, successful downloads averaged about 33 million per day, and successful installs averaged around 18 million per day."

The latest number from Microsoft (that they give publicly) for Silverlight downloads is from April of this year, when they were averaging 1.5 million per day.

Its probably worthwhile to look at the numbers for the Olympics recently and compare those to the number of installs for Silverlight. According to ZDNet, on day 3 of the opening weekend 3.42 million streams were watched online at NBC Olympics. Assuming that person viewed just two streams, that's about 1.7 million users - or about the number of installs that Microsoft could expect in 2 days (if they're completion rate is the same as Adobe's - about 54%, and assuming that every person watching didn't have the runtime installed.) And the same number that Adobe receives in 2 or 3 hours.

When it was first announced that NBC would be using Silverlight for the Olympics, many people thought this would be a great catalyst for distribution of the runtime. I had different thoughts at the time, and I think they've proven to be true.