They are ordered chronologically, most recent first.

I was thinking something like the following, purely to differentiate which 'today' something was learned on, or more to the point where I'd read up to :)

[Date/time stamp]
*  Item 1
*  item 2
...
[download]

Ok, good idea... It turns out that the mechanism already knows where you've read up to; so I could add an indicator showing that.

Update: Done. But it's a little crude. I'd like to make it highlight the new rows. Gotta find a suitable class for that.