Why GnuZilla?

[Christian Herenz]

Hi,

As a Debian User I use Icedove, Iceweasel and Icecat. So these are
GPL'ed versions of Mozilla Products, right?

I understand, that the GnuZilla Project has made some minor tweaks to
the original Firefox, but is that the only reason for having a different
project?
And why is it, that gNewSense on the other hand uses another GPL'ed
version of Firefox?

The only usefulness of this diversity is  to raise curiosity of some
people like me, I think. Wouldn't it be better to bundle manpower beyond
those projects to maintain one GPL'ed version of Mozilla Products, maybe
under the hood of GnuZilla? Or were offers in those directions neglected
by some party? Just curious - maybe somebody could elaborate on the
situation here...

Greetings,
Christian