Google Analytics Subdomain Tracking

Curious to know what WP experts think of the google analytics tracking code customizations for subdomain tracking suggested below:

"The purpose of this post is to provide my recommendations for Google Analytics subdomain tracking as of the current version of the asynchronous Google Analytics Tracking Code.

Currently there's no specific article on Google Code dedicated to Google Analytics subdomain tracking.

I propose... for the vast majority of sites with subdomains, you should use the following:

//Tracking code customizations only
var _gaq = _gaq || [];
_gaq.push(['_setAccount', 'UA-12345-1']);
_gaq.push(['_setDomainName', 'example-petstore.com']);
_gaq.push(['_addIgnoredRef', 'example-petstore.com']);
_gaq.push(['_trackPageview']);

http://www.roirevolution.com/blog/2011/01/google_analytics_subdomain_tracking.php