If you plan to use display none to hide content then be careful. ralph.m is correct, if it is in the html code, the search engines can see it even if it is not displayed to the user.
The problem with this, of course, is that it’s not great for accessibility. Anyone with JS off will see nothing, and screen readers will ignore anything with display: none; so it would be good at least to check that the JS overrides this for those devices too (I’m not sure about that).