Twitter co-Founder Ev Williams explains the reason for this in great detail on his EvHead blog. The argument for the change is that tweets will be unedited (they often have to be at present to allow characters for the tweeters name), they will be correctly attributed and you wont see multiple retweets because “You will only get the first copy of something retweeted multiple times by people you follow”. This fundamentally misses the pont. By seeing multiple retweets you get a real sense of the saliency or level of interest in a particular tweet. No-one rereads them all. Another problem with the new retweet system is the very absence of the retweeter – except in the metadata, and there is no guarantee that twitter clients will show this metadata. The identity of the retweeter is important because it is an endorsement and the value of that endorsement varies according to who is providing it…what if you get a retweet from @stephenfry or Ev himself but lots of people never see it because @joebloggs got in there first?.
Finally retweeting is not a concept originated by Ev Williams, Biz Stone or indeed anyone at Twitter it was originated by the community and belongs to the community. Ev says in his post “I know the design of this feature will be somewhat controversial”. My guess if that users will continue to retweet in the way that they do now and ignore the retweet function on twitter.com, and if they do this new feature will prove to be a real misjudgement. Fail.
PR and the Social Web 