How is using Google Tag Manager (which is a pixel container) different from using Floodlight tags?
The Tag Manager is actually a container that can load custom tracking tags as needed, whereas Floodlight tags ARE tracking tags. But as far as I know, the load of custom tags can be accomplished natively by Floodlight, through the use of what they call "dynamic" tags.
Floodlight Dynamic tags
Google Tag Manager
Cheers!
Here's the answer from the Google Tag Manager FAQ:
Today, many DoubleClick customers use Floodlight as both a container tag and as a conversion-tracking and remarketing tag. Because Google Tag Manager offers more versatile tag-management technology, we encourage all Floodlight users to install Google Tag Manager and migrate their existing Floodlight tags into Google Tag Manager using the built-in Floodlight template. This will make adding future Floodlight tags easier, and it will make variable collection much faster and less error-prone.
It’s important to note that Google Tag Manager does not replace the conversion-tracking and remarketing functionality of the Floodlight tag. DoubleClick users should continue to use Floodlight for these capabilities. Because of the more sophisticated container features of Google Tag Manager, we also encourage Floodlight users to migrate the tags in the Default tag section into Google Tag Manager, but to keep tags in the Publisher tag section within Floodlight to take advantage of last-click and view-through tag firing.
Does that answer your question? If not, let me know and I'm happy to answer any follow ups.
Cheers, Laura