As far as I can tell, it isn’t, it’s an option. Using ‘scons’ still works on my install. I think it is so that you can still build, regardless of which version of SCons your particular OS supports.
The excerpt from jesterKing’s commit log:-
This means that from now on one doesn't need to install SCons explicitely. Instead,
the user can now start a build by doing:
This way people won't have to worry about what their OS of choice offers for SCons
support - they will always have the latest supported SCons version at their disposal.
If necessary, one can always keep using their own install (provided it is supported
by our build scripts), by giving the normal scons command.
You did update SCons to 1.1.0? I guess now that the devs have upgraded we all must follow suit, and this will allow some sort of backwards compatibility. (Though only if you read the commit logs - which I don’t - Thanks again Sanne).
(Actually come to think of it, it does stir a vague memory, maybe it was mentioned somewhere)