Client deadlines

I spoke with a guy at church today who said he got a website done but it has never gone live because he just hasn't gotten around to writing the copy. In fact, he said it's been about a year and a half since the site's been done!

I wanted to post a question: what should be an acceptable deadline to receive copy for a website? 2 weeks, 1 month, etc. What is the norm in the industry?

I've always found that this is the biggest slow down to site development - waiting on copy from the client.

Anyone else have this issue? How did you resolve it? Is there an industry standard for dealing with this?