I don't know if there are any hard and fast typography rules on the usage of "and" or "&" in body copy or in headlines/taglines. Aside from simply being consistant, what guidelines do you follow when using either the word "and", or the ampersand glyph?
I think the only time you really shouldn't use the ampersand would be in a straight up journalistic context (newspaper headline) or in any paragraph of copy. Pretty much any other context would be a matter of personal preference, aesthetics or space constrictions. But definitely be consistent!