I would like a visual calendar of when jobs ran.

I would use this to quickly plan downtime on short notice.

I could pull up the calendar and find times when jobs were not running.

I would tell the sysadmin that he could take down the systems during the window.

You could do interesting things like color code the times with if the job failed.

You could implement this on a web interface so it would not change core code.

There is a way to visually view upcoming jobs in a calendar view. It odes not show previous runs though...
Under the tools tab, calendar, you can see Day, week, or month views. You can also select what jobs you see in that view.

Works great.

The run history would be a nice add, but this works great.