A bit of link bait really. I don’t thing that any journalist who doesn’t use Twitter should not be a journalist.
But I do think is that if you have heard of Twitter but haven’t tried it then you should be thinking about what kind of journalist you want to be. Even if you try it and think it’s a complete waste of time.
You could substitute twitter with anything from trying RSS feeds, Plurk, Qik or starting a blog. Whatever it is you have to engage and you have to engage for yourself. If you don’t engage, you aren’t punishing your employer, you are limiting yourself.
I’m convinced that if you are journalist who isn’t curious about the web then you you may find yourself seriously limited as the industry shifts or worse still, not being a journalist for very long.