I don't know if there is a general 'way' to register for this. I know that the JDeveloper and ADF use some 'intelligent' crawler to pick up blogs on the web which contain content for JDev or ADF. So, in this case, you have nothing special to do, but to wait. The crawler will eventually pick up the blog and add it to the list.
Other spaces might use a different configuration. If you share the space you are talking about I can try to find out what to do.
I am not sure if it is too late too respond.
My knowledge on this subject speaks that you should have a keyword specifically #Oracle#ADF and with a concpet like IOT(based on personal experience and not speaking with any authority)
It will pick up your blog to be displayed.
I asked same question on tweeter @Jdeveloper and they replied-
Simply tweet with the tag #JDeveloper and the URL to your new entry each time you have a new blog and we'll pick it up.
and i do the same and they pick my blog.
Seems to be a kind-of-desperate strategy to collect and build a list of blogs (quality review by anyone ?)
Hemant K Chitale