Delta RPM status?

[Jonathan Dieter]

What is the current status of delta RPMS?  I've developed a python 
implementation that can create a byte-for-byte duplicate of the update 
RPM from the delta using a modified bsdiff algorithm, but apparently 
I've been duplicating others' work.  My implementation works on a 
file-by-file basis rather than archive by archive and will work even if 
configuration files have been changed (by storing said files in patch as 
new files rather than as deltas).  It also can either use the user's 
file-system or an original RPM as it's source for applying the delta.

However, I realize all this may be a moot point if there's already 
something out there that provides the same functionality.  I hope I 
haven't stepped on anyone's toes.  Thanks,

Jonathan