Quote From TreeofLife:
This is a very old post but I'll still reply.
It does make a difference in your viva. If you have a paper published, it shows you're punishable, so they find it hard to justify failing you in a viva, even if they want to based on your performance or thesis.
I think you meant 'publishable'! Although, that being said.....
I think it depends on what you want at the end of your PhD as well. I am in Psychology, and have more interest in clinical practice after my PhD than academia, so I'm not that focused on publishing (although it would be nice!).