Another issue that comes up with external links is how they should appear in Wikipedia.
I'm dealing with that now with the local library linking templates I announced here not that long ago. I created templates that would give links as inlined text, and a template that would give the links organized in a box.
The last of these is visually distinctive, and it's the one that everyone who's added the templates (except for a few of mine) seems to be using. I think there are some good reasons for that, given their multi-library linking functions, and the special visual demarcation that also is common practice for certain other library-related external links.
But there are arguments the other way as well, some based on reluctance to have lots of box-clutter for external links. So the continued existence of the boxes is now up for debate in Wikipedia. Since many of you on this list may well be more familiar with the Wikipedia community and issues that I, I'd be interested in your thoughts. You can find the debate to date on the Library resource box template Talk page:
http://en.wikipedia.org/wiki/Template_talk:Library_resources_box
John