Glad to hear it's working well for you.
No blocking method is going to be perfect since the marketers always will try to work around them, but we think Nomorobo is the best solution available right now. It blocks the vast majority from our testing.
BTW, here's a little more info on it:
http://finance.yahoo.com/news/nomoro...153929450.html
We were the first provider to directly integrate their service.
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