The beauty of Google Tasks is it lives alongside your email, integrates seamlessly with the calendar, and automatically synchronizes across devices. The interface is super simple and intuitive (drag/drop for prioritizing and simple completion), yet powerful enough to allow for things like setting up recurring tasks.
I especially like scheduling tasks for items I know I have coming up a week or so out. When I know I have something coming up, I just enter the date/time and a description and I'm done. (Maybe all of 10 seconds?) It's so much faster than trying to put something in a calendar and I find myself offloading all of these things I have to remember from my brain and just rely on my device.
It has been very freeing. :)