betterC current consequences

[Amorphorious]

The docs states

Consequences
As no Druntime is available, many D features won't work. For 
example:

     Garbage Collection
     Thread-local storage
     TypeInfo and ModuleInfo
     Classes
     Built-in threading (e.g. core.thread)
     Dynamic arrays (but not slices) and associative arrays
     Exceptions
     switch with strings
     final switch
     synchronized and core.sync
     Static module constructors or deconstructors
     Struct deconstructors
     unittest (testing can be as usual with the -betterC flag)

The predefined version D_BetterC can be used for conditional 
compilation.

Are each of these still valid statements?

Also, is the GC os independent? I see there is an os module for 
the gc, but does it require the os for any particular reason?