I have been using Twitter on a regular basis as an experiment to see if my search engine rankings have made an impact on my position in the search engines.
One factor that I have recently read in many blogs is that Google is fighting spam on tweets the same way in combats spam when people link to websites with irrelevant content or have content on their website that is not relevant to the subject topic. It makes sense as any-one can tweet the same topic over and over and it should not get any ranking. Moreover, total duplication of tweets will push your site further down the search engine rankings.
One major factor of Twitter is it brings people to your website and therefore increases inbound linking, book marking your site, retweeting and viral marketing through the promotion of increased traffic to your site.
Microsoft and Google have signed agreements with Twitter giving each company rights to measure tweet traffic in real-time facilitating real-time search engine results.
Therefore, your twittering should be considered an important factor when optimising your website…people will come to your site because you offer something they want. Furthermore, factor in your content strategy, the subject topics you choose need to be relevant to your website content.