Norfolk Pine - OK for kitties?

I just picked up a small Norfolk Pine to use as our Christmas Tree. Are these dangerous to cats at all?

Most web sites (eg. petplace.com) say that Norfolk Pine is poisonous for cats. Petplace says that it is "moderately toxic -- chewing or ingestion can result in vomiting, depression, pale gums and low body temperature".

I have a norfolk and a cat (one year old -the cat!) and she seems to ignore it. I imagine any cat with a bit of a clue would leave it alone after just one nibble. Suppose it depends on the cat. Mine tends to go for any trailing sort of plant (drat!)