After reading about other peoples' experiences here, I don't see me regularly playing anything other than AV. Not with a full 5 man team anyway. Maybe I'll sneak into AB / WSG with a duo, but nothing more.

After you kill the same player 3 times (maybe 4?) you get ZERO honor for killing them... for the rest of the day
There always seem to be misunderstandings about this, which always makes for "interesting" discussions in BG chat

From http://www.worldofwarcraft.com/pvp/honorguide.html:

Subsequent kills: Killing the same character multiple times within 24 hours is subject to diminishing honor returns. Each subsequent kill after the initial kill yields 10% less honor, until the reward eventually reaches zero. Note that the Honor calculations that appear in-game do not take these diminishing returns into account.
It's a real shame the in-game honour display doesn't take account of it - it'd avoid alot of confusion.