I've been a bit busy lately with a new Android project I can't talk about, and I'm also overdue for an update to Greed I've been working on with someone.
This update won't really have much effect on you if you're a user, but if you're a developer, you can launch Greed for a specific feed ID now with code similar to the following:
String feedId = "feed/http://fognl.blogspot.com/feeds/default"; // or similar
startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("rss://" + feedId)));
If Greed is installed on the phone, this code will launch into Greed's Article List for the specified feed.
Note that the feed ID has to be part of your list of subscribed feeds in Google Reader, or Greed won't know what to do with it. When I have more time, I would like to make Greed smarter about this scenario, and add a subscription for the feed.