You probably have to worry about hypertext in content websites (search engine indexable) but for rich web apps, pure JS UI seems to be a good option. GMail's hy

You probably have to worry about hypertext in content websites (search engine indexable) but for rich web apps, pure JS UI seems to be a good option. GMail's hypertext is totally messy. As for urls and bookmarking, HTML5 history api can help (Github source navigation)