Get around UAC? Kind of missing the point here
'The Firefox team is testing a "Windows service approach" to get around the UAC issue; the service would install an optional component that would automate the update install without giving the UAC prompts, Bondy said.'
Chrome gets around this by running with user privileges in the user folder. What Mozilla are suggesting seems to punch a hole right through a rather important security layer. One small coding bug now makes the entire Windows platform vulnerable to malware, all to prevent a pop-up every 6 weeks.
Something tells me that this would NOT be the preferred solution for Enterprise. The preferred solution for Enterprise would be a pre-packaged MSI update that they could control the deployment of.