Dynamic retargeting for Shopping Ads typically relies on various advertising and e-commerce systems to deliver personalized ads to users who have previously interacted with a website or shown interest in specific products. Some of the key systems and platforms that allow for dynamic retargeting in the context of Shopping Ads include:

Google Ads (formerly Google AdWords): Google Ads offers dynamic remarketing campaigns specifically designed for e-commerce businesses. It uses data from your product feed and website visitors to create personalized product ads for users who have shown interest in your products.

Facebook Ads: Facebook's dynamic ads for e-commerce businesses can automatically show the most relevant products to users based on their browsing and purchase history. It's a powerful platform for reaching users on Facebook and Instagram.

Shopify: If you're running an e-commerce store on the Shopify platform, it offers built-in tools and integrations for dynamic retargeting. You can create and manage retargeting campaigns directly from your Shopify dashboard.

Magento: Similar to Shopify, Magento provides tools and extensions that enable dynamic retargeting campaigns for e-commerce stores built on the Magento platform.

Adobe Advertising Cloud: Adobe's advertising platform includes dynamic creative optimization features that can be used for retargeting and personalizing ads based on user behavior and preferences.

Criteo: Criteo is a specialized retargeting platform that focuses on delivering personalized ads for e-commerce. It uses machine learning and real-time data to show the most relevant products to users.

Bing Ads: Bing Ads, Microsoft's advertising platform, also offers dynamic remarketing capabilities for Shopping Ads. It's a good option for reaching users on the Bing search engine.

AdRoll: AdRoll is a retargeting and advertising platform that supports dynamic ads for e-commerce businesses across various channels, including web, email, and social media.

DoubleClick by Google (now Google Ad Manager): This ad management platform provides dynamic creative solutions for retargeting across Google's network of websites and apps.

Amazon Advertising: If you sell products on Amazon, their advertising platform allows for dynamic retargeting to reach users who have viewed or interacted with your products on the Amazon website. The specific platform you choose may depend on your e-commerce setup, target audience, and advertising budget. It's essential to set up and optimize your dynamic retargeting campaigns carefully to maximize their effectiveness and ROI.

If you're looking to run a behavioral retargeting campaign, you should place the pixel just before the </body> tag on the pages that matter to you. In most cases, ecommerce sites will place the pixel across their entire site and try to bring back all possible customers. However, depending on your business, you may want to place the pixel on pages that show a strong intent to purchase, eg the top of your shopping cart funnel. This will lead to a smaller prospect list but most likely higher conversion ratios.

You can see some additional information in AdRoll's retargeting FAQs - http://www.adroll.com/help

Chango is a retargeting company. They offer services such as A/B testing, advertiser logins, audience extensions, creative design services and frequency capping.

I am not too familiar with omniture but retargeting is an excellent way to reduce shopping cart abandonment. If a customer leaves your site without completing their purchase, you can stay in front of them wherever they go and remind them to return to your site and convert. This website might be helpful http://www.retargeter.com/.

One type of behavioral segmentation is grouping customers by search behavior. What does this mean? Let's start with two groups. Group one consists of the visitors on your site who load up their shopping and leave. Group two consists of visitors who click around, window shop and then leave.

Group one is more likely to make a purchase because they took their "search" a bit further. So, you can take this into consideration when marketing to this group.

How so? One option is a retargeting campaign. Retargeting attracts visitors back to your site, shortly after they have left by placing your banner on the next site they visit. There are agencies that have been mastering this particular online marketing strategy (such as http://www.adroll.com) for awhile. Of course, this is only one approach to segmenting your customers, but it can be a very effective component in any online marketing plan.