well no it won't hurt you because a link is always a link but it won't help you either because it has a PR 0 but they can help if they are coming from quality source like forums. Please add to my reputation if you liked my suggestion.
It will help you as long as you don't link back from a page that has a PR. However, if they don't have a PR and they are banner from Google, it won't help you. The only thing you'll get from the last one is maybe extra visitors but no search engine advantages at all. Also you should keep in mind that these sites can have a PR once google updates it's pagerank. Didier
if you target PR, PR0 will hurts you. but in a way that PR0 contains a quality link or related to you, this will give a benefits on you in other way.
if PR is your main concern then PR0 might hurt you if you link back to them. but then again a link is still a link.
if now they have 0 pr in future pr will increase and then will help you. there are no bad backlinks, only if the link that you have made link exchange is banned from google or other search engine than can appear some problems
yes help you. if your site not link back to that site then it definitely help your site ranking as well as future backlinks. Don't look present pr0 it can be changed any updates and if your link found every indexing then it'll give more importance for the creation of backlinks.
There are so many confusing conflicting and wrong answers in this thread it's unbelieveable! Firstly sites linking to you (in moderation) can't hurt you. The only exception is when a site suddenly generates hundereds of thousands of incoming links and is 'Google Bowled' Though this is in extreme circumstances. PR0 links can help, with a couple of exceptions. Firstly the page itself has to be cached by Google - they have to be aware of the page before they are aware of the link to your site. Secondly check that the site the page is on isn't PR0 because it's been banned, serach for the sites URL in Google to see if it's included in the index. Also a link from a completely unrelated site isn't going to help much at all, try to make sure incoming links are from sites that are related to yours.