Formats supported

rpm5.org now has an extra mailing list: rpm-lsb . Right now the archives show just one
message:

http://rpm5.org/community/rpm-lsb/0000.html

Jeff Johnson writes there that he wants to document the format of rpmv4 (which is the one
actually used today) well enough so it could be used in the LSB specifications. He hopes "to
start in mid-January, and have a completed document by the end-of-March or so."

And he's not completely alone. While Mandriva has decided to use the original rpm recently,
there are still a number of distros that use rpm from rpm5.org .
See the following thread:

http://rpm5.org/community/rpm-devel/index.html#1824

Disclaimer: I don't follow closely rpm.org or rpm5.org .