Calendar evolutions

Hi,

I'd like to have the option to use calendars on a personal basis (similar to MS Project-style resource calendar).
This is for easier planning: team members could enter their holidays well in advance, even if they haven't confirmed their dates yet. For example, if someone knows that they will be taking roughly two weeks off in the summer months, they could easily grey out two weeks in their calendar.
If these dates are confirmed, the user will enter these days as 'holidays' in Real Work Allocation (RWA), making it official. But if the dates change in the end, the user can also log work on other activities, confirming that his holiday dates have changed.

So it would be : calendar used for easy planning purposes (medium - long term), and RWA used for official accounting.

In the current process, this is possible using only RWA, but the user interface makes it easier to use in the Calendar view.
Also, the Calendar feature can support this - all that is missing is some access rights management (ability to configure access so Team Members can edit only their own calendar, but PL can edit any TM's calendar), and perhaps an optional "resource" field so personal calendars can be identified.

What do you think ?