I think I have a better "simplistic" view of MP-BGP...
This is how I keep it straight or understand it in my head:
- Address-family VPNV4 is used for PE to PE, to exchange VPN routes - implying that multiple VRFs will cross these peerings.
- Address-family IPV4 VRF XXX is used for PE to CE, to exchange IPV4 routes with the "customer" - implying that the interface connecting to the CE is in VRF XXX.
If this isn't right, I hope someone corrects me :)