I like these, and I think they make my online interactions a little more complete, because I can signal, in conversation, where I would laugh if it were a face-to-face interaction, for example. But there's one I struggle with: *hugs*
Offering hugs in a face-to-face situation is meaningful and significant. A hug can signal any number of things: support, sympathy, excitement. And there's a bit of a tendency to use it for the same thing online, especially, I've noticed, here on LJ. In fact, a lot of times, someone's entire response to a post will be *hugs*. And while a hug may feel like a complete response to something in person, I find them fairly empty online, when not accompanied by other context. Don't have anything else to say? Try *hugs*!
Therefore, I've been conducting a little lj experiment with myself for a few months: no *hugs*. Whenever someone writes a post where my first reaction is *hugs*, I think about what it is I really want to say, and try to put it into words. Sometimes it's more successful than others, but it's certainly been interesting for me, and, I think, has meant an improvement in the quality of my comments, at least from my point of view.