New setting for "type" of feed email - subject only, subject plus summary, etc.

Request:
It would be great if you could set a "type" of feed email. For example, "Email subject only," or "Email subject plus snippet", where a snippet could be 100-200 characters of the full story.

Reason:
Some of my subscriptions are for application trackers. For example, I subscribe to the feed for macupdate.com, so I don't miss if there was an update to an application installed. The problem is, the feed email contains the full feed contents, so in any given day, I get the full listing for 30-50 updates. Each update item in the feed contains a full description, notes, etc. So it might take a very long time to scroll through the entire feed email.