Brands and their respective digital PR and social media agencies should look to strike and continually refine the optimal balance between how much content to share and how frequently.
Overshare, the description given to over exuberant usage of a service meaning that the user rapidly distributes post after post of content, has affected a great many passionate social media users at some point. Foursquare, the location-based service, even rewards users with an 'OverShare' badge, for a high number of discrete check-ins in a short space of time.
The alternative is also problematic, with brands or businesses that do not engage frequently enough simply not making best use of a service and failing to capitalise on the commercial opportunity.
Many social media users - myself very much included - go through something of a love affair with a service before becoming a heavy user. Part of that love affair involves heavy use of the service to learn about its strengths and weaknesses, its opportunities and pitfalls. Consequently, it's very easy to find that one has distributed a good deal more than what might be determined normal usage in a very short time period.
As a user, the worst case scenario is perhaps only that one irritates one's followers - which is perhaps not a major problem during the growth phase. However, in learning from this phenomenon, it's easy to see how brands that do overshare really do jeopardise the fan equity that has been built up through otherwise considered and tightly managed usage.
Whilst it's clearly somewhat different from one sector and one business to another, best practice seems to suggest that brands should look to post two to four times per day in Facebook, with a significantly more frequent schedule acceptable for Twitter. Google+ remains something of an unknown, as it is currently in a honeymoon phase with many users and brands have yet to be invited onto the platform on a widespread basis. It's likely that a frequency more akin to Facebook - i.e. two to four per day - will be more appropriate than one similar to Twitter.
Ultimately the community will be a key indicator of what's appropriate in this or any other service, although technological or algorithmic factors, such as Facebook's Edgerank, which determines what content is shown to which Fans of a page, also play a vital role. It will be interesting to see whether Google does allow the community to decide what is and is not appropriate in terms of frequency, or does go down the same route as Facebook by introducing a filter.