Hi,
Debian releases have 25,000 or so packages and don't include the source
to them, so to recompile the package you use apt-get to connect to the
internet and download the source to one package at a time if you want
the source code. I did some calculations to see how much bulk adding the
package source code to the debian release would add and using high
compression it appears that it would increase the overall release size
by less than 1%. Most users won't care or benefit from having the source
code to these 25,000 packages included in the distribution, but some
will probably like the ability to be able to have this source code and
be able to recompile packages without requiring internet access to
download package source code.
Here are my calculations, they are rough estimates:
packages included in Debian 4.0 /etch/ (283 million lines of code)
source: http://en.wikipedia.org/wiki/Debian
assuming 32KB per 1000 lines of code, this would be about 8.6GB for 283
million lines of code.
assuming a factor of 100 for the compression of this code, this would
give approx 88MB of extra space required in the debian distribution for
all of this source code.