I believe player radar has been a feature for a while. Players show up as blue dots on the map. Per Rei's page, under "How to Enable Cave mapping / Entities radar on SMP", "&2: entities radar (player)" is listed as an option. As I said previously, the message can be sent by granting it with bPermissions, and has been done previously, so I expect to see it enabled for next rev.
1. I'm sort of on the fence on this. Even though I allow TP by default, I still would like to know who TPs in, which is only displayed if you're in ask mode. Before I was sort of relying on player radar to tell me, but that's not really as good as a bright green message stating it explicitly. As for what mode for default, I still think ask is good, but with a message for the first few times telling the player they can change it to allow or deny if they'd like. I don't really want to see people saying "you're in my house, and I didn't invite you" at random times.
2. My observation doesn't really pertain to next rev, but reenabling grass spread means we don't have to build NerdBukkit anymore (since the only difference from regular CraftBukkit is the disabling of grass spread). It's one less thing to worry about when updating.