Mike, the setup of the Smart Collection is separate from the Export preset, but the cool thing is that you can still set up the SC to make it "work together" with the export.
Basically, what I've done is create a SC such that all images that lie within a given folder name belong to that SC. Let's make this concrete. I have an export preset that takes the selected images and exports them to disk in a specific folder, called "snapshots for web". These exported images are also automatically added back to my catalog (this is specified in the export preset). Then, I have a Smart Collection whose sole rule states that only the images that lie within a folder named "snapshots for web" belong to it.
So, in practice, what happens is that when I want to take a bunch of snapshot pictures and export them, I select them in the library (e.g., in Grid mode), right-click, and choose my "export snapshots for web" preset. Basically a one-step operation. Don't have to worry about adding them (manually) to a collection or folder since LR will now take care of that automatically.
Whenever I want to see all the web-sized snapshots that I've exported, all I have to do is click on the Smart Collection called "snapshots for web" and there they all are. And of course collections & smart collections are visible in all modules (aside from Develop) so they're pretty much accessible from everywhere.