Xubuntu, the Xfce Ubuntu flavor, will ship with a 1GB ISO starting with Raring. Obviously, after this change, Xubuntu will no longer fit on a CD but this will allow some packages that were dropped in Xubuntu 12.10 to be added back by default.
One of the main reasons for this change is the "amount of developer time currently spent keeping the ISO small enough to fit on a CD". The 1GB ISO change was brought up in a recent Xubuntu team meeting and the votes were 8-0 in favor of raising the ISO size to 1 GB.
The Xubuntu team has also decided that with Xubuntu 13.04 Raring Ringtail, GIMP and Gnumeric, which were dropped from 12.10 because there wasn't enough space, will once again be installed by default in Xubuntu.
See also: Xubuntu 12.10 Released With Xfce 4.10 [Screenshots, Video]