I agree with Daniel on the mechanics of failed communication, and
think any blaming of either side is wrong as well as
counterproductive.
However, I think the basic request to NOW communicate widely which
namespace range should be reserved for site-specific purposes is very
reasonable.
Of course their will be not contract, but the present situation is
unsatisfactorily. On
http://www.mediawiki.org/wiki/Extension_default_namespaces
their is no recommendation where to set up your site-specific
namespaces. The page says that 100-199 is often used, and extensions
should avoid it, but actually some of the most important extensions
happily invent their namespaces there.
I don't believe it has to be a 100-block, but a clear commication to
all devs: in the future, at all cost, avoid x-y would be welcome.
Gregor