A feature that would allow you to ask the Wiki, "Show me all Changes that I haven't seen yet". For example, say you go away for a month or so and then come back and want to see what you've missed. At first this seems easy; just look at RecentChanges. But of course you won't be able to catch up in one or two days, and after that, if you are a RecentChangesJunkie, you will find that the top of RecentChanges contains new, recent changes, followed by a lot of changes that you have read, followed by changes that you missed during your absence. Since you don't bother to keep track of where the boundaries are, you eventually forget about the missed Changes, and, being a RecentChangesJunkie, are forever haunted by the possibility that you missed something particularly interesting or relevant (relevant, e.g., did someone answer a question of yours somewhere?).
As a WorseIsBetter shortcut, instead of actually keeping track of such things, a system on the wiki for remembering the boundaries (there may be multiple boundaries if you go away a lot) and filtering RecentChanges accordingly would be nice.
Perhaps the best place to do this, though, would be not be in wiki software but as a feature of ChangeAggregator software.
When you know ahead of time that you will be leaving, there is a solution, however:
:Only if you are away for less than the KeptPages time limit. Anyway, the real problem was keeping track of the boundaries between what you've already read and what you haven't caught up with yet, after you've gotten back and started to go through the old Changes. – BayleShanks
As for the KeptPages time limit, the entries in the ChangeLog? will stay for a very long time; the only thing you will be missing is the ability to view the diff – when you click the diff link, it will say "diff not available, showing current version" or some such. I don't really understand the second part, however. You leave at t1, come back and start reading at t2, and then take a break and come back at t3. My solution will show you all changes from t1 to t3; are you asking for all changes between t1 and t2? (I already thought about that, but haven't implemented anything yet.) – AlexSchroeder
The way I've envisioned CatchUp working is having a list of all visitors (signed in visitors) associated with each page. Each entry in the list keeps track of the time of their most recent visit and perhaps a count of how many times total they've visited. Given that this information is stored, you can filter recent changes to show only pages that: 1. have changed in the last X days, and 2. you haven't visited in the last X days. Another potentially useful filter is to show only pages that: 1. have changed in the last X days, and 2. you visited more than X days ago. This second filter only shows you pages that you've been to before.
The part I really like about remembering when a user most recently visited is that you can highlight the differences between the version they last saw and the current page.
I really like Brandon's idea of CatchUp here, even though RSS is one type or work-around. RSS isn't as good because sometimes you read from RecentChanges instad of RSS and then need to wade through the feed later to Catch it up with reality. Yuck.
This wiki has tons of feeds, because basically any kind of filtered recent changes can also be served as an RSS feed. Some meta information is hidden in the HTML to allow for self discovery. Your browser should detect it automatically; look for the link element with rel="alternate" and type="application/rss+xml" attributes. If you need to find a feed that is just right for you, click around on RecentChanges until you like what you are seeing, and then change action=rc to action=rss. Check Oddmuse:Rss Action (which also links to Oddmuse:Rc Action) for the real docs.