Just thought I'd share a quick tip: When cropping/composing an image in photoshop, zoom in and out between thumbnail and preview sizes (that the microstock sites show) so that you can optimize the 'curb appeal' of your images.

Do you mean optimizing the image for the thumbnail size? For that you would have to sharpen to much right?

No - I mean making the image look as attractive as possible at preview and thumbnail sizes.

Given the overall fussiness of most reviewers, I no longer sharpen my images.