As "The Hybrid" comes to an end, with Klaus despairing over his failed plan to create a hybrid army, he tells Stefan that he is the only companion left. Perhaps the writers didn't need to be so explicit about this fact, but it speaks volumes about his character, that failing to make his army leaves him alone and without purpose. He'll go on and try again, but this initial defeat is as crushing as it gets.
What surprises and makes me happy about The Vampire Diaries is that all have great parity as they develop despite the obvious differences in screen time. Jeremy's ghost story doesn't get much more than a few scattered scenes, but the end result is more or less where Stefan plot is, interesting and forward-looking. Vicki shows up and tells Jeremy that she can come back, then Anna shows up and tells Jeremy not to trust Vicki. With a couple quick lines, everything is thrown out of balance and we're left wondering what's going on.
Elsewhere in Mystic Falls, Tyler reveals his lycanism to his mother in an intense scene, and Caroline is chained up by her father. Lots of stuff moving ahead which I'm sure the writers will tackle head-on.