If you're looking for something that does it all, then take a look at Daylite for the Mac and Daylite Touch for iPad and iPhone. Daylite does a great job as a contact / calendar / task / project / and information manager all in one, and syncs well with the mobile platforms. I comes with a built-in server app that allows you to keep all three in sync using dyndns.org if you don't have a static IP. I used it for about a year and a half.
Unfortunately, it does all of the functions well, but OmniFocus does task management REALLY well. And in my business life, task management and project management are very important. I don't mind using separate apps to achieve what I need as long as they all are the best in what they do, I'm not willing to settle for less. I use OmniFocus, OmniPlan, BusyCal, and Address Book to do what I need.
Last edited by atreinke; 2011-11-07 at 03:04 AM..