Archiving (Archivable.h)
BBufferIO
New BBufferIO class inherits from BPositionIO.  A BBufferIO acts as a data buffering mechanism for a BPositionIO object (a BFile, typically), thus turning stream data into buffered data.
To use a BBufferIO, you "attach" a BPositionIO object to it in the constructor, and then invoke the Read[At]() and Write[At]() functions on the BBufferIO object.  You can set the size of the underlying buffer in the constructor; the default is 64k.
Class Info
The functions in support/ClassInfo.h have been deprecated.  Use the C++ RTTI functions instead.
BLocker
By default, a BLocker uses a benaphore for its lock.
The new BString class is convenient, lightweight string allocation and manipulation wrapper.
Miscellaneous
Defined in support/SupportDefs.h