There are other options available. What almost certainly happened here is that Google was so concerned with getting the features right that they pushed it out

There are other options available. What almost certainly happened here is that Google was so concerned with getting the features right that they pushed it out without asking "What could go wrong?" A lot of startups do that and most of the time they're fine because they can learn as their user base grows. But Google made a strategic decision to bind Buzz to Gmail and that is what caused the problem. The lesson is that a lot of people are thoughtless when building technology but once you get to the size of Google you can no longer afford to be as lax as everyone else.