A new report from Vitrue has analyzed data on Facebook to determine when is the best time of day to make a post. After studying more than 1.6 million posts, 7.56 million comments and 1,500 brand streams, it boils down to this: Wednesday at 3PM ET.

It is, Vitrue, said the consistently busiest period. In general, it found that  the best usage period were 11 AM, 3 PM and 8 PM ET.

If such metrics sound familiar that is because they are: email marketers have debated ad nauseum when the best time is to send an email. The conclusion reached by many is that the clock is irrelevant in terms of what really matters: whether that e-mail eventually result in a sale.   Simply put, some questions are just not worth asking, Loren McDonald of Silverpop recently wrote in a blog post. "There are no truly meaningful answers for these questions, but more importantly they simply are the wrong questions to ask," he writes. Instead, it is better to ask such questions as ‘What are our revenue or other business goals and therefore what email process metrics are required to achieve these goals? How do we create e-mail programs that add value to the customer relationship and maximize conversions and revenue? How do we send more relevant e-mails, more often but with the same or fewer resources?'"

So can this measured approach be applied to Facebook as well, or are marketers condemned to a similar era of analyzing and debating the minute-by-minute reactions of their posts and offerings? Unfortunately the answer may be yes - although it may not be necessary to be as precise as Wednesday 3 PM ET.

Facebook is different from email, to state the obvious, with consumers spending increasing amounts of time on it. Inside Facebook recently reported the total amount of time spent on Facebook by its users on the site is up from 500 million minutes in late June to 700 million - a surge that is most likely due to the increasing size of the user base. Other engagement counts are also up, it noted, pointing to the now 900 million "objects" that Facebook users interact with, up from 160 million in June, a stat that presages the launch of the new version of Groups, which means it is likely to go up even more as users experiment with that feature.