Update 12/11/2012: And we're back to gnome: http://www.phoronix.com/scan.php?page=news_item&px=MTIyNTM
This is a bit of a bombshell: http://www.phoronix.com/scan.php?page=news_item&px=MTE1NTk
Also reported here: http://www.h-online.com/open/news/item/Debian-to-use-Xfce-as-its-standard-desktop-1663868.html
and here: http://www.neowin.net/news/debian-drops-gnome-chooses-xfce-as-default-desktop
and here: http://linux.slashdot.org/story/12/08/08/1455243/debian-changes-default-desktop-from-gnome-to-xfce
UPDATE: No, I don't have any more information. However, I've been thinking a little bit about this. Debian is not a targeted distro like Ubuntu, Red Hat, SUSE or Mint. I'm not sure how the discussions among the debian package maintainers go, but I'm suspecting that it's more of a matter of ironing out reported bugs, than to focus on providing a 'user experience'. SID and Testing are rolling releases, after all. So 'dumping' gnome really won't affect anything at all very much in the short to medium term. Those who like KDE will use KDE. Those who like Gnome will use Gnome. And so on. In the long term, enough people may encounter XFCE as their first DE via Debian that it starts to change the balance in the user bases of the different DEs, but given that a great majority of both current and future debian users come to debian via other distros -- from red hat/fedora/knoppix back in the days, then ubuntu in the late 2000s, and now perhaps mint -- many users probably both have both experience in how to set up different DEs and preferences as to which one they want to use.
So yeah. Sorry about the hyperbole in the title.
Basically, Debian is thinking about dropping Gnome as the default desktop and replacing it with XFCE when Wheezy goes stable. The official reason is (CD ROM) space, not that there's any issues with GNOME 3.
I wouldn't be surprised if the rumoured difficulties in communicating with the Gnome crowd may have played a role, in addition to the (a bit hysterical at times) general dissatisfaction with GNOME 3.
Having 'grown up' with gnome (Baby Duck Syndrome) I think it's sad news -- gnome is pretty, functional and makes linux just different enough to give it a distinct look.
[Btw, this article about the Baby Duck Syndrome is a nice read: http://www.ibm.com/developerworks/web/library/wa-cranky50/index.html ]
XFCE, LXDE and KDE are all capable desktops, and I've played with LXDE and KDE recently. Not being that familiar with XFCE -- or even LXDE really -- it does appear to me that what really sets KDE and GNOME apart is that they come with a complete package -- KDE and GNOME all have their awkwardly named software applications: epiphany vs konqueror, evolution vs kmail etc.
Apart from lxterminal and lxmusic for lxde, and thunar for xfce, similar DE specific apps appear to be thin on the ground for LXDE and XFCE. That's not necessarily a big issue, but we've all had issues with GTK vs QT and how pieces of software using either framework look in different environments. It's hardly a disaster, but just enough to be noticeable.
It would also be interesting if the netinstall and business-card isos would ask about which specific DE to install, rather than just ask about whether a desktop is to be installed , in particular if debian is interested in experimenting.
Offering more choice would really not be that bad of an idea. Personally, and for my own biased reasons, I'm much more interested in LXDE than XFCE, and more interested in GNOME than KDE. XFCE, the way it's implemented in Debian Squeeze, looks a bit dated -- basically like GNOME 2. While I'm not really into that, given the uproar during the past year a lot of people seem to prefer the old gnome 2 look. Besides, the strength of the old desktops is that you can theme and modify them to the point of no recognition.
And if we're talking about slim installs of debian, we really should take a look at Crunchbang (#!) as well, which uses openbox.
Finally, what about Jessie? Will GNOME be back or is this the defining moment for XFCE?