We're building a new website platform and are using Ajax as the method for allowing users to select from filters. We want to dynamically insert elements into the URL as the filters are selected so that search engines will index multiple combinations of filters. We're struggling to see how this is possible using symfony framework. We've used www.gizmodo.com as an example of how to achieve SEO and user-friendly URLs but this is only an example of achieving this for static content.

We would prefer to go down a route that didn't involve hashbangs if possible.

Does anyone have any experience using hashbangs and how it affected their site?

Any advice on the above would be gratefully received.