[latchkey]

I don't know about 'best', but I certainly can tell you what we've done for our latest project, Voost. https://www.voo.st/

Google App Engine cause we hate doing sysadmin work. Objectify. Cambridge Template Engine with JEXL. RestEasy/HtmlEasy. Jackson. Guice to bind it all together. Front end is heavily CoffeeScript, Handlebars, Jquery, LabJS, customized bootstrap and various other libraries. We've got a credits page full of links to the above projects... https://www.voo.st/about#credits

Overall, I'm pretty happy with this choice. We've had to do some weird and semi-complicated stuff to integrate it all together, but at this point, it works quite well.