Our Comparison Shopping Engines Survey Report published this week found that there has been an overall increase in the level of online retail sales that can be attributed to this channel.
The research, based largely on a survey of retailers and sponsored by DoubleClick, puts the spotlight on the benefits of comparison shopping engines (CSEs) at a time when consumers are sharply focused on bargains.
We have previously written about how comparison engines have tried to re-invent themselves as "product comparison" sites rather than "price comparison" sites, so it is something of an irony that their orginal raison d-etre - a focus on the cheapest deals - is putting the wind back in the sails of the major CSEs.
For most retailers, visibility on comparison engines seems to make perfect sense, providing that they are driving profitable and incremental sales.
Most retailers are getting the message that it is worth trying out this channel, with 63% of retailers now making sure that they upload feeds to Google Base to ensure visibility on Google Shopping and Product Search.
(Because this is free, you may well ask why the other 37% aren't doing this, especially when Google Product Search had 1.9 million unique users in September 2008).
However, while many retailers are dabbling with the odd comparison engine, only a quarter (27%) are uploading feeds to six or more CSEs.
Because this space is very fragmented, it requires a broader approach than PPC where most companies will happily put their eggs only in the Google basket.
Another report finding is that 59% of retailers are not using online marketplaces such as Amazon and eBay to market their products.
The main reasons that the vast majority of retailers are failing to take a systematic approach is the time-consuming nature of optimising feeds for numerous CSE and marketplace sites, and the difficulty of measuring RoI.
The good news is that CSEs have made it easier to provide feeds although retailers are still turning to third parties to take away the pain (13% are now using feed optimisation specialists).
But what's clear from talking to the major comparison engines is that there are still well known retailers out there who are not even doing the basics when it comes to submitting feeds, and who express surprise when the channel doesn't deliver for them.
There is a wealth of information in our report for those who want more data on this subject.