It will be very nice to have a block list feature on obi talk. This can be the list which can be maintained similar to 'trusted number' on obitalk. Once a number is added to blocked list, obi AA should catch it before routing the call and terminate it(this of it as 'circle of distrust')
and if you can add "on the fly" blocking of a number then that will be super cool. Eg. while the call is going on, user can press a number(e.g **0) which should add the current number to blocked list and maybe play a message " You have just been blocked" and terminate the call. :-)
What do you say?