Thomas: Needing to manually SIGHUP means we are misbehaving elsewhere, unfortunately.
I've been doing some work on trunk which should prevent us leaving (python and gtk) references to the vte.Terminal objects and thus never GCing them.
poolie: could you branch lp:terminator and confirm?
(stealing the bug and marking In Progress pending confirmations. It seems ok to me, but it's late and there are lots of codepaths at work)