I am a web guy doing mostly Perl server-side stuff, and I\'m slowly coming to a few conclusions.
Since there is no well defined API and a best library for templating, I would suggest you choose one that is actively developed. Below, I briefly explained two libraries that are actively being developed.
jQuery team decided that jQuery Templates will no longer be actively developed or maintained, thus I would strongly suggest NOT using it. See this blog entry.
You can use JsRender in accordance with JsViews to take full functionality provided by jQuery Templates and even more like data linking. You can find demos for JsRender and JsViews. I would suggest using these libraries since they are actively being developed by jQuery UI team but be aware that they are still not even beta!
Mustache is another templating solution that is actively being developed and it simplifies templates by combining conditional tags and enumeration tags. It also provides strong features like inverted sections, partials and high order sections with simple syntax. Mustache is also one of the fastest templating solutions See blog by Brian Landau. I, personally, find mustache a good templating solution since it has a simple syntax and performs well.