Looks good, Matty, thanks. But I think a better approach than replace is urlencode, like we do in master:

https://github.com/ginatrapani/ThinkUp/blob/master/webapp/plugins/insightsgenerator/view/_email.insights_html.tpl#L7

I'll change it in my merge. I'll also add an assertion re: the icon, and a urlencode for network (so it's not broken for "facebook page" in the future).