I think Jamie makes a very good point, Google Base / Merchant Centre / Shopping (all the same thing) is an incredibly valuable tool which is hugely underutilised, although it's worth mentioning that it's not suitable for all businesses.
If your product range consists of many different lines of mass produced product, meaning you are likely to be up against a lot of competition on each particular product line then it is a fantastic way to get noticed.
If you offer a bespoke, tailored, hand crafted or otherwise unique product then it will be of very little value to you.
The reason for this is that, if a Google user searches for a product such as "twinings earl grey green tea" (try it!) then google sees that the user's search closely matches a lot of merchants' google base listings - so it inserts a widget at the top of the search page showing the first 3 results (by relevance - same logic as a regular google search). If there are only a few matches in google base then the widget does not get shown.
If you are one of these first three results then this is invaluable, as you would most likely have to do a whole lot more work to get the same kind of positioning in the main body of the google search, simply because everyone is in the main search, while only a few businesses have taken the time to submit their product search feed.
This leads nicely into the real reason that this isn't more commonly talked about, in my opinion anyway....
Anyone who is already using this, web designers / developers / marketers included knows full well that it's success depends on it remaining undersubscribed - once everyone uses it, it becomes as crowded as a regular google search and therefore the added value is lost. Except for Jamie (!!) these people tend to save the benefits for themselves, and for their customers who are willing to pay a premium.
There is a whole lot more to be said about product search, such as the fact that it's API programming interface means that your products will show up on many other services such as the point and scan apps that are popular on the leading smartphones....
I'll have to google this some more, if this info really isn't out there maybe this is it... I finally found something worth blogging about!
Incidentally - whatever line of business you're in it always pays to be willing to step outside the box in the interests of customer care, so this is a totally appropriate point for a good web designer to be making. Wouldn't you expect a good windscreen fitter to mention if your tyres were flat?
Bottom line - if you are selling lots of standardised products then this is a cheap, quick and easy way to stand out on google. Well worth a try.
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