I've had Bento (now in version 3) for the Mac for at least two years now. I've played with it but never have gotten to the point of where I felt like it was a comfortable tool to be using. But that's changing now that I've spent some time tinkering with it. And you know what? It's actually pretty powerful and, there's an iPhone app that can link to the databases you create on your desktop so you have ready access to the information all the time.
This is really the best project management tool I've used in a long time, and now that I've figured out how to manipulate it and do so creatively, my eyes have opened to a lot of potential.
Yes, it will keep your iCal and Contacts folders managed. No biggie there. But when you start adding time tracking for projects, information about certain aspects of a project, timelines, etc. then you've really got a pretty cool tool in your hands.
Not much more I want to say about it right now. But if you have a Mac, this is worth giving it a test drive.