What if I don't want forum news on the portal page and I want custom content?
Your other option is to create a custom forum just for content to display in the portal. You could probably make it hidden from the main category list so it just appears in the portal page.
I Haven't tried it but it does state in the "Forums to pull news from:" settings:
Note: This ignores user groups, so anyone will be able to read these items regardless of their permissions.