AV and WG for me.
I just love the epic feeling of AV it truly feels like a war between factions trying to take out the others leaders. And the same is true for WG my server is almost always packed with anywhere between 2-4 raids full. Many of the matches are close and hard fought which makes them that much more fun. And the fact that we are fighting over a shot at the Vault guys makes the weekend nights very interesting with multiple guilds showing up to try to get there shots at the big guys that night.
There are still some places WG could be improved such as the lag, the rank cheating and tenacity balancing but it is overall my favorite pvp BG these days... especially since they have awesome rewards also!