Thank you for your post.
At this time, FileMaker Pro and Bento do not talk directly to one another. The best way to get share information between FileMaker Pro and Bento is through a comma-separated values (CSV) text file, which both Bento 1.0 and FileMaker Pro import and export. With Bento 2, you have a couple additional formats. In either case, you just get the data; not the forms/layouts.
There is a utility made by third-party developer called FMPro Migrator that supposedly does transfer Bento databases to FileMaker Pro, but I have not had any experience with it. The developer's name is David Simpson, and you could search the web for more information.
FileMaker Pro does not interact directly with Apple's Address Book (like Bento) unless you purchase a third=party plug-in. If you search our web site (www.filemaker.com) for "Address Plug-in", you will get a few listings that should point you in the right direction.
If you need clarification for any of the above, please let me know.