Hi Alexander,
Yes, I have seen that as I subscribe to the Google Analytics blog.
There are several challenges to changing to this async model, the best we could do easily is implement the split script approach mentioned here:
http://code.google.com/intl/ru-RU/apis/analytics/docs/tracking/asyncUsageGuide.html#SplitSnippet
which retains most of the benefits of the async approach.
The other issue is backward compatibility for existing sites which may have javascript snippets already entered in the content system for custom tracking. For example I have many places where I track things like referrals to consulting partners and other external links where I have added javascript to the link to track the click like this for example:
<a class="fn org url" href="http://i7media.net/mojoPortal.aspx" onclick="mojoPageTracker._trackPageview('/ReferToi7Media.aspx');window.open(this.href,'_self');return false;">i7 Media</a>
so it would be problematic for me to find all these in my content and replace with the new async syntax and others may also have existing tracking snippets.
What I am willing to do is make 2 new controls GAnalyticsAsyncTop and GAnalyticsAsyncBottom so we can implement an option for the async approach without breaking any existing tracking using the old approach. I will let you know when these controls are ready and you could test for me since I do not want to change my site. The idea would be to remove the existing one and replace it with the bottom control and also add the top control just after the opening form tag in layout.master.
I have not had any problems using the traditional approach and I think this async approach is a micro optimization. Recently I watched all the videos on the googleanalytics channel on YouTube http://www.youtube.com/googleanalytics I learned a lot that helped me get better reporting, especially about advanced segments. I highly recommend watching all these as they were very helpful. But one thing I noticed is they mentioned how they soft launched the new async script approach but are not pressing hard for people to change to it and they will never get rid of the traditional way. But in any case I will try to implement support for it with the 2 new controls and hope that you can test it when it is ready and make sure it works correctly.
Best,
Joe