Ok, tested moving from a 0.8.4 VPC to a new one. Big changes:
You have to update your Private/Public subnets to be a list now, it'll fail with a string (though this is by luck only, we really should make it so that a variable w/ a list type only accepts lists, not basestring)
Two things got updated: the DHCP Options (just because I consolidated the name) and the NAT external IP - I can't understand why on the latter, but I'm going to keep investigating.
Makes using NAT Gateways the default as well.