I noticed a little widget appears in the menubar....kind of looks like a pair of binoculars on a scroll...you can kick 'em off from there I think and also shows IP connected from.
For others with the same question you need to enable the menu first.
Go to System Preferences->Sharing.
Click on Remote Management.
Click on the Computer Settings button.
Make sure the Show Remote Management status in menu bar box is checked.
That way you will be able to see and kick anyone off that is sharing. I would still like it to notify me somehow when someone is sharing rather than have to check that menu...
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How can I tell if someone is sharing my screen?
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