When embedding a Team Calendar macro in a page, there is option to include multiple calendars in the embedded view. However, there is no key (as there was in the old calendar macro), to distinguish the variously-colored entries from one another. The only way to determine what the difference is between the purple entries and the pink entries (for example) is to click on an entry of each color and read the description. There should be a way to quickly at-a-glance see what each color means.
It doesn't necessarily need to look like the old key. The key could just have a small colored box with a description next to it. It could be above or below the calendar. If you want to save space, it could be a slide-out panel from the side of the calendar, or even a simple "Key" button which opens a pop-up key in a modal window.
Just some suggestions, but I think a key is really necessary.