Sync iOS5 reminders between people using iCloud How can Reminders in iOS5 be shared between two iCloud accounts?  In other words, how can two users send or post to other users a Reminder?
The other user (@Paul) is incorrect! Create a list that you want to share using your iCloud account. On your Mac, click "Reminders" to the side of the calendar view in iCal. Right-click on the calendar you want to share, then click "Share Reminder List..." On the menu that appears, select "Only the people you invite" and click Ok.

Easy and effective!