For a good primer on what an RSS feed is or what it means to subscribe to a site, check out this page. I also wanted to offer a bit of a public service for others in my circle of friends. though.

I'm on LiveJournal but have non-LiveJournal friends I want to keep track of when they update

You can create "feeds" for those other friends and get their RSS feeds mixed in with your friends list on LiveJournal. All you have to do is add them here by adding the URL of their RSS feed: http://www.livejournal.com/syn/

Some of the most common formats/examples for the feed URL:

TypePad: http://leofwynne.typepad.com/adventures/index.rdf (it can take some poking around to find the right link for this, holler if you need help) DiaryLand: http://thornbury.diaryland.com/index.rss (DiaryLand feeds have been sporadic at best and just started working again on Friday) Other: http://www.wilwheaton.net/mt/index.xml (Wil Wheaton rocks. He uses Moveable Type and has his own domain etc.)

If you add a URL that no one has added before, LiveJournal may ask you give it a name. You are naming that feed for everyone who uses LiveJournal, so be sure you give it a reasonable name that implies where it's coming from (like thornburydl or leofwynnetp or doocefeed) and not something obscure (like mysweetie). In addition to your friends, you can add a variety of news or public service RSS feeds. For example, I added the Word of the Day feed and the American Diabetes Association News feed to my friends list. You can see the feeds I have in my user profile in the section under the satellite dish looking thing.

As a note, when you first add an RSS feed, it will dump all of them at once to start, so your friends list may look like a bomb hit it at first. This will sort itself out soon enough.

I don't use LiveJournal, but would also love to keep track of various RSS feeds

You can use a Feed Reader like NewsGator, or the like. The free one is a just a web site that you go to, but you can pay a small price for it and get versions that work on your phone or integrate with Outlook.

You can use the formats above as well as add any LiveJournal user. The format for any LiveJournal user is:

http://www.livejournal.com/users/puck_eater/data/rss or http://www.livejournal.com/users/puck_eater/data/atom

depending on if you want RSS or Atom. Your mileage may vary.

I've noticed some of my feeds show the whole entry and some just show snippets with a link.

This is something the RSS author (or their provider) has set up. Each author has their reasons for doing that. Some do it to make sure they still get traffic to their web site (and thus, those ever so satisfying web stats), others just do it to save space on your reader (like a lj-cut in LiveJournal). Again, everyone has a preference one way or the other and they both have their strong points.

I notice your RSS feed link at the bottom of your web site isn't any of those formats. What's up with that?

I use FeedBurner to manage my RSS feed, becuase I'm a stats whore. I also want to be able to change the link behind the scenes for my blog if I needed to, one day, and not have to change where folks go. It's also nice that FeedBurner gives a short tutorial at the top. And I can use FeedBurner to have the same link be my PodCast address (PodCasting is a whole other post in and of itself). My link is:

http://feeds.feedburner.com/messageinabottleblog

If after reading this, you still have questions or comments, let me know. I'm just doing my part to get all the various folks to easily be able to keep track of each other online.