So far in this thread, there has been a fairly even split between folks who think PR should be ignored versus folks who don't. I personally think PR should not be ignored, and my advice to Sheppy is also to wait for your PR to recover next update, and build content in the meantime.
I just gave a link to a grey PR site, and I am worried about doing it, but the other webmaster insisted that his site is just too new to show PR. ( he has all his text in H1 tags + CSS formatting. )
I'm giving the guy the benefit of the doubt until after the next update, but I feel like I'm taking a risk AND being generous... while the other webmaster seems frustrated, needy and not grateful enough.
In more general terms, whether or not one chooses to believe that linking to a PR-grey or PR0 page is risky (for associating with a bad neighborhood), I think the other concern, that weights more heavily, is the issue of inequitable PR trades.
When talking about reciprocal linking (and not just linking for a users benefit), then balancing the value of PR gained and lost is a consideration for many webmasters.