As per the Steve Chen's blog post, this is due to:
a) Wrong URL settings on the managed meta data service application.
- The content type hub was set on URL http://sp2k10a/sites/CTHUB/SitePages/Home.aspx
- This URL was also set in the MMS app
b) Missing entry in the AAM’s
- The MMS web service was listening on address http://hostname:32843/... But in AAM settings we only had a map to http://hostname:4000 which is the CA
The solution to tackle this issue is (depending on where you already are with your scenario) to:
1. In your Content Type Hub site collection- create some site columns you wish to include in a content type;
2. Create a desired Content Type and add newly created column(s);
3. In a newly created Content Type settings, try to publish- received error? Read on...
4. Go to Central Administration -> Application Management -> Manage Service Applications and highlight 'Managed Metadata Service' [top link above Managed Metadata Service Connection]
5. Once highlighted, click 'Properties' on the ribbon and scroll down towards the end of page
6. Input the URL of your Content Type Hub Site Collection making sure you exclude /sites/home.aspx or any other suffix after the domain name.
Make the URL look like http://intranet.domain.com
7. Check 'Report syndication...' and click OK.
8. Being back on the Service Application page, highlight a 'Managed Metadata Service Connection' and click 'Properties' on the ribbon
9. Check the 'Consume Content Types from the Content Type Gallery at...'
11. For 'Content Type Hub' and 'Content Type Subscriber' [subscriber for a required Web App], run the jobs immediately to push all of the changes:
12. Now, go back to your Content Type Hub Site Collection and re-attempt to publish a content type in question;
13. No errors? If you still see some error, most likely you need to correct your URL to make sure it has nothing after 'domain.com'.
14. Navigate to any other site collection -> Site Settings -> Site Content Types and verify a newly published content type is there!