It's common to find all the various osteoporosis drugs confusing when it comes time to compare and contrast -- or switch. Here's some information that might help you sift through it all:
Reclast vs. Fosamax, Boniva and Actonel
http://www.healthcentral.com/osteoporosis/c/73/13598/reclast-acid/?ic=4004
Forteo: Do the Benefits Outweigh the Risks?
http://www.healthcentral.com/osteoporosis/c/73/2677/forteo-risks/?ic=4004
Fosamax, Actonel, Boniva: Why Might You Be Prescribed One Oral Bisphosphonate Over Another?
http://www.healthcentral.com/osteoporosis/c/73/8029/boniva-oral/?ic=4004
Alternatives to Estrogen for Osteoporosis: SERMs in Development
http://www.healthcentral.com/osteoporosis/c/9487/26055/alternatives