Very interesting question Donnie. Although pretty simple, it's a little complex at the same time.
Here's what I am thinking: It does make sense to have it unique on every PR, somewhat related to the theme of your PR. However, it's an about us...not about the PR. I think although right from the SEO perspective, it might not be 100% right from a PR/business standpoint.
My mind is also relating this to the fact that if we have a header and footer on every page, it's the same/duplicate content. Should that not be unique then ? I think Google is way past these things. Google understands what duplicate content is (to a very great extent) and I would not worry about it if you are doing less then 10 press releases a year. However, if you are doing something like 1 press release every week for the client, then it might make sense to have a relatively unique copy written.
But before you decide, I suggest you discuss it with a PR professional. Sometimes, for us, it get's difficult to think outside the box (SEO Box :).