From my thread here: http://forum.mikrotik.com/t/sofware-vlan-bridge-on-ruteros-explained/122534/1
I was trying to understand new way to do bridging.
If I do understand it correctly the new Bridge with VLAN filtering do handles Spanning tree (STP and RSTP), the old did not.
https://wiki.mikrotik.com/wiki/Manual:Interface/Bridge
It would be nice if MT post a list that shows what is the best way to do VLAN. Birdge with VLAN filtering and hardware support, or use the Switch chip.