Call or chat with Verizon and have them double check your provisioning. They have the ability to see what your ONT is set to, and can re-provision it if the speed is not set right.
To be sure, with the 150Mbps package did Verizon give you a Revision I ActionTec router? Do you have an Ethernet WAN connection back to the ONT? Also, have you enabled any features that could bog the router down, such as parental controls?
You can test against Verizon's own speed test too, to get an idea of whether or not the problem has to do with provisioning or something further out on the Internet. http://speedtest.verizon.com/