Managing the number of personal and business contacts you have can be a really hard job, especially when email addresses keep changing, people get married, etc.
Contactizer 3 Pro (previously known as OD4Contact) is an all-in-one solution for managing, sharing, and organizing your personal and business contacts. Designed specifically for Mac, it looks great and generally makes dealing with contacts a lot easier, although it is a big package and can take a little getting used to. On startup, you're prompted to go through a lengthy setup process where you can configure Contactizer 3 Pro to import existing contacts, sync with iCal and apply other options.
Afterwards, the launching of Contactizer 3 Pro is very slow. It took around 30 seconds for the program to launch, during which time I thought it had crashed or simply didn't have a GUI. The main interface takes up your whole screen and looks similar to Address Book but with several more features. While the program is supposed to sync with iCal, I found this problematic, and unfortunately there isn't much help documentation, although there is a lively forum.
Overall though, Contactizer 3 Pro is a highly-accomplished package that will meet the needs of anyone who requires a serious contact management app.