Does a tool exist to share UAT feedback?

The problem you have is a common one. Testers working in different time zones and in different groups can uncover the same problem and submit duplicate reports.                                                                                                                                            

I agree, the tools that Matthew suggested will certainly work for you. I have found that when a project is small, simple tools work fine. However, as the project grows in size and scope, time spent manually managing simple tools can grow accordingly. At some point, you may want to look at a more sophisticated integrated tool. I personally like Confluence wiki. You might get some ideas from this document. http://getzephyr.com/insights/best-4-collaboration-tools-agile-software-....