Overcooking Photos

Photography is going through now what typesetting went through when the Mac came out. If you're old enough, you remember when people made documents with every damn font the Mac had, with horrible results. Now we have photo processing filters and tools and presets and crap, so the web is littered with:

• Black skies with white clouds.
• Oversharpened everything, with weird little halos and creepy looking highlights.
• HDR. Ugh.
• Instagram. Ugh.

All of this stuff is fine in moderation. Darkened skies are a time-honored tradition to make the clouds punchier, but if what you notice is "the sky is black" rather than "the clouds are lovely!" you've gone too far. The same applies throughout, if what you notice is the effect, not the image, you've gone and ruined your image.
A good image will be a good image without any effects at all. Post-processing should serve to enhance and improve the image, to enhance drama that is already there, to highlight the important parts, to draw the eye in so the image can engage the viewer's mind.
A bad image, or even an uninteresting image, with a bunch of post-processing effects added to it, is still bad or uninteresting. The effects may be eye catching, the the viewer won't even see the image. Maybe that's what you want, but there's an easier way to ensure the viewer doesn't see the image -- don't show it to them!