...and can get you fired.
Minor adjustments in Photoshop are acceptable. These include cropping, dodging and burning, conversion into grayscale, and normal toning and color adjustments that should be limited to those minimally necessary for clear and accurate reproduction (analogous to the burning and dodging previously used in darkroom processing of images) and that restore the authentic nature of the photograph. Changes in density, contrast, color and saturation levels that substantially alter the original scene are not acceptable. Backgrounds should not be digitally blurred or eliminated by burning down or by aggressive toning. The removal of “red eye” from photographs is not permissible.
Just for those that want to learn the differences...
If you're doing something for yourself you have creative freedom to do anything you want - and mean pretty much anything as it's for you and nobody else, you like what you like in your photo illustration. If you're working for a client then you do what they want with your creative knowledge as well, in other words your vision under their guidelines - for example know one site that sells prints that has no problem with photographers removing red eye, by all means do it if they allow it and it makes for a better image, this would include prints for parents on personal sites. If working PJ or if someone like a newspaper asks for an image as they often do nowadays with citizen journalism there are more strict guidelines in place that you need to know. If you send it in and an editor does something like reducing red eye that's their decision - they'll often rename it "photo illustration", but that's their choice. Don't just listen to one persons bad advice of fix it in photoshop, know when and what is OK dependent on the situation - this is why many clients often ask for the RAW image to make sure nothing was done.