Specifically I'm asking about the concept discussed in the top rated answers in the meta post How to post links that integrate with the Software Center?
Once upon a time, when apps.ubuntu.com was up to date this was kind of cool. Currently however, none of the currently supported versions of Ubuntu show up under available versions.
Here's an example:
Granted this doesn't stop an apt link from working, but I can see a new user becoming confused and coming to the conclusion that the software in question is not available for their current version of Ubuntu.