Google has recently rolled out some improvements to the service, and Narayana Tummala at the Inside AdSense blog talks a bit about them:

It’s now up to ten times faster, and it uses much more historical data, so you get more accurate estimates of future availability. The new system allows us to quickly add new features in the future. We’ve already launched one of these improvements: Forecasts now take account of frequency caps, meaning that the availability estimates are modified to account for the fact that you might only want to show an ad once to each user. And more new features are coming soon!

Forecasting also continues to be a major development focus of our DART for Publishers (DFP) ad serving platform for publishers with larger direct sales teams, part of the DoubleClick Revenue Center suite of publisher solutions. Google Ad Manager serves as an effective complement to DFP and the DoubleClick Revenue Center to provide solutions for publishers of all sizes.

When it comes to forecasting, you must check your available inventory. When you do this, you can confirm when ad impressions are available before you book them.

According to the Ad Manager Help Center, if the check inventory query confirms that ad inventory is available, you can export the inventory query data into a line item in a new order or an existing order. With check inventory queries, you can optimize your ad inventory and prevent overbooking or underselling.

How do you check your available inventory in the first place?

Google provides you with a step-by-step process on how to do that here. There is also plenty more information available on forecasting, such as adjustments and troubleshooting here and an Ad manager FAQ here.

Ad Manager is something Google developed to help small publishers serve and generally handle ads.  Some upgrades have been made since it was first announced, with interfaces becoming available in 32 different languages.  Day and time targeting, along with automatic macro insertion, have been enabled, and users should look for all-important ad previews, as well.

 

As for whether the release is solid and/or useful – Google Suggest did, after all, languish in beta for about four years, and Ad Manager made it out in five months – it seems early tests went quite well.

Alex Vogenthaler explained on the Inside AdSense blog, "Thousands of publishers in hundreds of countries already serve billions of impressions each day with Ad Manager, and we’ve heard from them that Ad Manager has helped increase revenue, cut serving costs, and save time managing campaigns."

So, by using an existing AdSense account or creating one for the first time, uninitiated publishers will probably want to check Ad Manager out.  The sooner the better, too, since an official statement concerning the tool’s lack of cost is attached to the suspicious-looking phrase "at this time."

Senior product manager Rohit Dhawan writes, "Google Ad Manager is a free, hosted ad and inventory management tool that can help publishers sell, schedule, deliver and measure their directly-sold and network-based ad inventory."

"It offers an intuitive and simple user experience with Google speed and a tagging process so publishers can spend more time working with their advertisers and less time on their ad management solution."

The post states that dozens of publishers have been using Google Ad Manager in early trials and to hear testimonials about the service from those publishers you can visit Ad Manager success stories or take a product tour to find out more.

Google Ad Manager is still in beta is open to publishers by invitation only. You can learn more about it or be considered for the program by going to the Google Ad Manager site. As the program expands Google says it will include additional publishers and provide updates on its progress.
 

The ongoing limited beta test of Ad Manager at Google received more attention, as the company may be ready to open it to a broader audience of publishers.

Websites that do not require the complexity or options of an ad serving network like, say, Google’s newly approved acquisition, DoubleClick, will be able to manage the ad inventory they sell and the ads they receive from an ad network.

The Wall Street Journal said Google plans to announce the service, though a timetable was not mentioned. Through Ad Manager, publishers will be able to fill in gaps in their ad inventory with whichever network they choose.

Publishers will not be limited to Google’s AdSense with Ad Manager. Webmasters favoring other ad networks with more generous revenue shares may opt for them, though Google will be happy to supply them with text, image, or video advertising.