Just another item that Nathan missed. Those 3 "identical spheres" are actually 3 [i]different[/i] colors (obviously the sign of a person who's never given OS X more than a passing glance). If you were to point your cursor up to any of those points you will note that they clarify themselves even further than the colors. The red one shows an x, the yellow, a dash, and finally the green, a plus. Hmmm pretty similar to windows...
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