With release 8.5(1) the only way to get content like this into the system are RSS and authenticated RSS.

Suggestions:

1. poke around the site for RSS feed. Not all sites make this as visible so you also might try a full Interent search looking for an RSS feed from the site in question.

2. If RSS is not supported, then you might look at other services that can pull from that site an publish RSS. For example, Feedburner or even yahoo pipes which may be able to grab the site and publish an RSS feed.

3. Subscribe with email. Some sites don't support RSS but they let you subscribe to have notifications sent via email. Some email services support publishing emails as authenticated RSS. For example, the RSS feed for a gmail account can be found by logging into:
https://mail.google.com/mail/feed/atom

You can create an "Authenticated RSS" feed using this URL and the gmail credentials to pull emails into SocialMiner.

There may be a couple clicks to get back to the content (first click opens up the mail in gmail and second click goes to the site you subscribed) but this is a workable option with no development work.

4. (future) 8.5(2) adds a new feed type called "Push". This publishes a REST API which an app developer can invoke to push social contacts into SocialMiner. An application developer could develop middlewhere to pull content from a system and push it into SocialMiner. See post on the Cisco community for full list of proposed content for 8.5(2).
https://www.myciscocommunity.com/docs/DOC-20294