Yes. Well, any post on the Steem Blockchain regardless of domain. It can be a link to busy, dtube, zapple, decentmemes, etc. It just has to be tagged #steemit for now and it will look to see if the domain is a steem interface that I've approved- at least for now. Most of the interfaces in steemprojects.com is okay. Give it a try though. It's a work in progress.

Also, if you write about Steem on another platform (like medium or minds) and post it to twitter with the tag #steemit, it should get aggregated to me. Again, work-in-progress.