For nearly a week, Spurs center Tim Duncan has reportedly emailed his teammates invitations to join him on Googles new social networking site, Google+. Please join soon, as Ive already begun sharing game plans and upcoming events via Google+s Circles feature, Duncan wrote in an email Tuesday, adding that team chemistry may suffer if people dont have access to each others +1s. Ive pinned the San Antonio Spurs under my Sparks, and you should too as soon as youve set up your profiles. And, also, guys, please switch out your old Comcast and Earthlink email accounts for new GMail ones so we can communicate easier via Google Groups. As of press time, no Spurs player has entered Duncans current Google+ Hangout. 