The truth is that a significant number of news-based accounts are clearly automated, very often by the use of RSS, because Twitter has become more than just a place to send updates. It's infrastructure. And even if these accounts aren't automated through RSS, practically all of the top accounts are full of a stream containing only headlines and links, with Mashable being no exception. (See also: TechCrunch, Techmeme Firehose and ReadWriteWeb for example)
It's clear that while "The Twitter Rules" say that "If your updates consist mainly of links, and not personal updates" is one criteria for being labeled spam, it cannot be the only criteria. We must believe, and I do, that Twitter would know how to separate the good from the bad in this type of a case.
The truth is, and I have said this many times, that you should participate and make your data available where your audience may be. And often, even if you are initiating content in one place, the audience may be somewhere else - like Twitter. As a result, it makes sense to move that content to Twitter to give them access.
TwitterCounter Shows Growth for @lgshareditems and @scoblefaves
A recent experiment I kicked off on Wednesday was creating a dedicated Twitter account for my Google Reader shares and Delicious bookmarks at @lgshareditems. This combination has always been available on FriendFeed (and Facebook), but not Twitter. In parallel, Robert Scoble, also a guy well known for trying new things with social networks and data, has been tracking favorite tweets from those he follows with a dedicated account called @scoblefaves.
I have watched both accounts creep past the 100+ follower stage, even though both accounts are new, and both are exclusively feed-based. Each is a new way to try and utilize human filters and pass the results to Twitter, with the difference being that I am betting on content from outside of Twitter, and Robert is betting on other Tweeters. I bet both have strong value to separate audiences looking for news and tech updates - even though our data sets are different.
My shares to @lgshareditems are equally as genuine as my posts to @louisgray. While I may have more personal updates at the @louisgray feed, I do also post my new blog updates there, as well as my Delicious bookmarks, to give those authors additional exposure. And as noted above, practically every self-respecting blog and news source can see their Twitter feed to be extremely link heavy. So I expect it will take a lot more than you seeing a lot of blue underlines in my feed to be in danger of getting the big boot from Twitter, no matter what their TOS says.