The technology and culture oriented website Mashable has met a new milestone, netting some 100,000 users as participants for its new “Follow” feature. Launched in April, Follow lets readers keep tabs on topics of interest and share news with others in their social network.  Readers can tailor the subject matter they are interested in by clicking on the Follow button alongside an article or by hitting the Follow button on a list of topics. The green button also lets readers share content with their Twitter, Facebook and others in additional social networks in one fell swoop.