TL;DR: Don't panic, the single articles multistream bz2 file for big wikis
will be produced shortly after the new smaller fles.
Long version: For big wikis which already have split up article files, we
now produce one multistream file per article file. These are now recombined
into a single file later, wth a single index file in the fashion everyone
is used to.
This part of the speedup work mentioned in the previous email.
Have a good weekend,
Ariel