I just forwarded this to my boy, DJ Drooodson, as he is always on my case about not eating meat, and telling me that "plants are people too", etc. (he is just a pork addict in denial, if you ask me.) Anyway, here is his response to the article, which I found interesting:
While it's well known that plants communicate, even across different species, it's not really anything special. It's more a basic evolutionary response to things like predation and disease. If plants did not evolve these behaviours, then they would have all gone extinct. Fighting predation and signaling other plants that disease or predators are around is a basic survival strategy you can find in even the most primitive organisms, and has never been considered a sign of intelligence.
I do support the idea, however, that plants probably carry out functions analagous to various animal functions, but in completely "alien" ways we simply haven't considered. Can plants feel pain? Maybe not the same way we do, but being able to tell when your body is being damaged is a very important evolutionary benefit. Since plants don't quickly die, even if you destroy vital parts of it, then killing a plant will always mean a slow, and if it were an animal, a very painful death. Imagine taking weeks or even months to die if someone cut off your limbs or removed your vital organs. At least cows die quickly.
Plants are living things too, you know, that have responded evolutionarily to the same things we have. They just found different solutions.