Even after Wikipedia added "nofollow" attributes, Wikipedia traffic is greater. After searching wikipedia traffic in alexa on wikipedia search, from the traffic point of views there is no any affect either positive or negative side, the traffic is going on...
Traffic analysis after approx date of "notfollow attribute";
http://traffic.alexa.com/graph?o=l&c...=3&h=300&w=610
Google send tons of traffic to wikipedia and it is still a trusted source for google and other search engine for targeted traffic. It put great impact on
website hosting traffic. Users most of the time refer wiki, in my views even after "nofollow attributes" submiting your
website hostings to relevant Wikipedia articles on specific topic will greatly help in targeted traffic.