I was wondering how twitter could do all this for free, then it struck me they do not have to. All the people who used to frequent forums can choose to pay for their own adverts on twitter and by monetizing their own adverts they can choose to stop spamming or overtly trying to sell their own products. Here is a graphic I did to show the idea.

How Twitter can make money from tweets
By slightly changing the format of the tweets with a header and content above the advert paid for with each posting by the twitter user who chooses to or by a sponsor who pays by tweet.
This way twitter can charge for the adverts while keeping the service free of charge for those who just want to twitter their lives away.
This has advantages for the twitterers too, with the advert featuring a live link they get the benefit of the search engines such as Google being able to index the site, this will help to increase the sites reach and Gooogle will also get a benefits from it too.
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