When you have a lot of AJAX calls on your website, especially ones that return a list of data, it can be quite expensive processing time on the server to retrieve the results, format them with HTML, and return them to the browser to display not only that, your bandwidth costs can be quite high as well. With jQuery templates, you can alter your AJAX calls to return JSON, and then populate the content client-side providing faster response times and less server processing as well.

If you already have a lot of AJAX calls that return HTML, do not fear; it is not a lot of work to convert them to jQuery templates and improve the speed of your website. If you are just getting started, glad to see you're thinking ahead!