Current state of affairs:
1. Contacts is not tagged as a mature package and it will messs up all accounting related modules that depend on it. Unfortunately the dependancies are not clearly marked, so you may run into crashes if you decide to give it a try.
2. Can we mark contacts a priority, and set a deadline by which it needs to be fully functional.
3. Who's working on getting this sorted out. I see Malte and Thorben being involved in the topic. Are there other takers? Is there anything you folks need assistance with? I am sure some of the new kids on the block could help with moving forward.
4. Contacts relates to addresbook. Since that package has been depreciated 4 years ago, please remove it from the tarball. It's broken, and nobody uses it.