Apart from the obvious advantages of providing real-time data to other technologies, there's one "group" of users which have not been mentioned.

And that's web sites that are focused on dissemination of news, such as newspaper front pages (online) and portals.

Disclosure: I work with a product that provides exactly that, real-time click data to editors.

Workflow involves pushing out a large number of stories in an optimal way and responding to real-time data to decide the optimal positioning and life-time of each story.

Of course, some of the requirements outlined by Avinash still hold, like you need a certain amount of traffic for the data to be useful, and that data must be available in a readable form to the person actually executing the changes needed.

I am considering writing a blog post on real-time usage in this segment, if there's any interest in it.

With regards to twitter and real time search (i.e not a consumer looking for real time stuff but rather you as a company using real time search data to do something) I think you are falling in the trap again. What would you do if you have that data? Is it just that you want to know what is happening or you have the capacity to do something (either using automated systems or manual systems that can react very fast on your interpretation of the data)?

In every case actionability makes the decision for me. In 99% of the cases there is a yearning for real time data but absolutely no capacity to react to it. Then I would much rather the finite resources be used to do strategic non-real time analysis.

Tony: You are right, and it is because they are used to getting a streaming ticker of information to make decisions, often in real time (think currency arbitrage).

Web analytics is ten million miles away from that kind of a need or that kind of an action.

Knowing is not enough. The priority should be on knowing what you can to action in a timely manner.

-Avinash.

But it seems like this is not unlike the live-streaming switch we're seeing with Facebook and Twitter. I have found that the focus on immediacy has the tendency to draw my attention from the more important long-term work.

Typical scenario: I'll make a video or will write something. It will go up to Youtube, a blog, out to Twitter, up to my Facebook personal account and Fan Page. Within a few days my followers have left comments and retweeted. I'm in that warm glow of instantaneous feedback from people I know. But the audience I care about is actually not the people who follow me, but the people who I wish would follow me. They're not as likely to see the post immediately. They'll be coming in one at a time over the next few months or even years. My goal is to convert them into regular followers. You only see the mass of these stumblers in the aggregate when looking at data over time.

In short…
- real time for analysis, not relevant.
- real time for personalization and optimization, relevant.