Apparently due to popular request, and following the launch of tasks in Gmail Labs, Google has now introduced an integrated task list for its Calendar.

In Calendar users will now see a "tasks" link on the left hand side, that works the same as the one on Gmail, except for some calendar-specific additions.

Google says tasks that have due dates will automatically appear on calendars and that to create a task with a due date in Calendar, users need to click on an empty space in month view or the all-day section of week view, and select the "task" option.

More info, and relevant links, can be found on the Google blog.