Good question. I am using links like
[[http://www.google.com][Google Search]]
that will be displayed as "Google Search" in a buffer. The remaining
characters are hidden, using both invisible and intangible properties.
I am in the process of realizing that `invisible' will be enough to do
the job, and that `intangible' is not needed.
The reason why `intangible' is in there is because emacs-wiki does it
this way, and I learned from looking at this code. Anyway, I will
probably remove `intangible' from org-mode anyway, just need to
convince myself that is is safe to do so.