I recently read GTD and I am a total MAC geek, have been since the 80's. I've been spending time over the holidays (with a little time off) scouring the internet for best practices on GTD, especially those involving OSX. After many hours and days of work, my inbox is ZERO thanks to Apple mail.
I've been looking at Evernote, Reminders, and the other systems that exist for GTD implementation.
For me, GTD will be in full swing beginning Jan 2. So far, I am leaning toward Apple Reminders since it is so simple.
Just agreeing! Good luck.