It targets the huge and ever growing online shopping market in a very detailed way and that is niche product marketing and customization. You basically sign up with the largest retailers like Wal-Mart, Amazon and the like as an affiliate, then click and paste your affiliate link through ACS and place the created widgets on your website, blog, etc. However, as with many other legitimate programs, it takes for granted that you have a website, blog, etc. where you can place these widgets and that you already have visitors to your website, blogs, etc. in order to actually benefit from online shoppers purchases. But that should not deter you from actually buying it at all! It is a great instrument, especially to target specific products that have peak sales during a certain time of the year, like for instance Christmas.
The one and only draw-back, if you can consider it as such at all, is that you have to sign up with the retailers individually, whereas with ASN (All Solutions Network) you already have access to most of the world's largest retailers in one go, be it as a shopper and/or affiliate. Now the trick is to use ACS in conjunction with ASN. The reason being, ASN offers so much more for the online shopper, than the retailers individually! It shouldn't be too difficult and I'm working on it and will let you know in the next couple of days.
In the meantime check them out and you will certainly not be disappointed!