I don't know how many times clients have asked me to share 'numbers' with them for audience over my web career. While in the first web phase, having big numbers of visitors was important, we're starting to see that smaller, more intimate conversations are now more crucial as the web continues to offer more two-way interactions for communications and gestures.
Andy Beal has cited a few indicators of engagement or activity, which could include conversations, responses, frequent returns, high levels of clicks and communications.
While traffic on my blog is still an indicator of success, I find checking the amount of time people actually spend on specific posts, and what that post content is about is actually more interesting that large visitor trends.
If you're seeking what to measure, check out this list, or see a list of companies that may help your organization out.
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