Good start, but ideally networks should also be required to provide originator info (number, network, country of origin, as many hops as available basically) to cell phones, regardless of whether a call is blocked or has a different number set as caller id.

So not only would the networks be blocking spam, end-users could then block whatever calls they want. Don't wanna get calls from any VOIP numbers or anyone out of your country? You can block them and chill out.