I have a client site running under the root domain, e.g. without www: http://example.com.
However, the client requested that URLs be shown with WWW on the Google search results page. The actual URL used when accessing the website should still not show the WWW.
I have gone and updated the settings accordingly in Google Webmaster Tools, as outlined here:
https://stackoverflow.com/a/5963681/278840
This has been done around 2-3 months ago, yet Google still shows the results without the WWW.
Does it really take that long for this change to propagate across the SERP, or is there something else that I have to change?