Our advice on whether the Tag Manager is relevant for you
Although it's a significant new feature for marketers from Google, this tool isn't relevant for all businesses. I'd advise that you don't need to worry about this tool if you're not investing heavily in display advertising or affiliate marketing. If most of your visits are currently referred by direct visits plus paid or natural search, social or email marketing it's likely overkill and the basic Google Analytics tag setup is sufficient to track and report these through Google Analytics.
However, for larger companies and their agencies managing complex sites using a range of media investments to drive visits it could save a LOT of time (and expense from using paid tag management solutions). With this new tool, Google have taken a another step forwards in giving more power back to corporate marketers, reducing reliance on development resource. For example, it will make easier to add advanced analytics such as a new tag for re-marketing or the Doubleclick Ad network or the implementation of affiliate network tracking code. It will also make it easier to assess the value of media since de-duplication is also possible.
This short video from Google will give you a great overview:
So what is it? And how does it work?
As most people will have installed Google Analytics at some point (or at least asked someone to do it for you) you will remember the little bit of code you have to include on every page of your website.
If you ever then want to use Google Remarketing, Double Click, setup ecommerce tracking or even your own custom tracking from tools like affiliate networks or similar you would need to add further code, sometimes to every page other times just to specific pages. This was the dilemma Google saw and why it came up with Google tags as a "master container" that you can implement all tracking codes in one simple interface without ever having to update the code on your website.
6 Steps to setting up a container
Step 1 visit www.google.com/tagmanager/
Step 2 name your new container
Step 3 enter your domain(s) as needed
Step 4 copy the one bit code onto every page of your website
Step 5 add other tags as you need too
Benefits of Google Tags
The Google Tags is great tool for any website / marketer that needs to implement multiple tracking tools without any coding knowledge or the desire to ask a development team that might book it in for 3 weeks time. Examples of other tracking facilities you could include within a Google tag are:
Affiliate tracking
Double click
Remarketing
Behavior targeting systems
CRM
Tags is primarily aimed at large online sites that are running multiple systems and tracking codes to aid marketers and where access to a websites code is restricted and tied down to time draining processes etc. Most smaller websites needn't worry too much about this new functionality it is likely you can just stick with standard Google Analytics code and you are generally a little more agile
There are also options to use it in more advanced analytics using Event Tracking. Thanks to Dan Barker who has created this example on Google+ to illustrate this. This will fire a Google Analytics event that captures the product category, product name, product value and stock status, and to only do that when a visit hits a product page (not a real world use-case, but a good illustration).
Agencies
Just as they have with services like Google AdWords, Google have designed in the ability to manage multiple accounts. You can read more about multiple accounts here.