The enhanced feature set of the 802.1w standard includes:
Bridge Protocol Data Unit (BPDU) type 2
New port roles: Alternate port, Backup port
Direct handshaking between adjacent bridges regarding a desired topology change (TC). This eliminates the need to wait for the timer to expire.
Improvement in the time it takes to propagate TC information. Specifically, TC information does not have to be propagated all the way back to the Root Bridge (and back) to be changed.
Origination of BPDUs on a port-by-port basis