I've been working on this for a week since upgrading. The new roles and capabilities system is really outstanding.
However, with the upgrade, my writers were able to see the email addresses and IP addresses of commenters through their dashboard using Manage/Posts or Manage/Comments.
I've come up with a slight modification that will solve this problem.
First go get the very excellent plugin "Role Manager".
Follow the instructions there to install the plugin. Be sure on your plugins page after activation the plugin version is 1.3. I had problems getting earlier versions to work.
Ok, now go to Users/Roles in your dashboard.
Scroll down to the "Contributor" section.
Make sure that "edit posts" is checked with a green check mark. Make sure that "read" also is checked with a green check mark. Now change the userlevel to 0.
Concurrently you will need to slightly modify the menu.php file in your admin folder.
menu.php in case you need to revert back.
menu.php find the following line:
$submenu['edit.php'] = array(__('Posts'), 'edit_posts', 'edit.php');
Change it to this:
$submenu['edit.php'] = array(__('Posts'), 1, 'edit.php');
Now find the following line:
$submenu['edit.php'] = array(__('Comments'), 'edit_posts', 'edit-comments.php');
Change it to this:
$submenu['edit.php'] = array(__('Comments'), 1, 'edit-comments.php');
Save the file and upload it to your admin folder.
What this does.
Now users you have given the ability to write posts, but NOT post them will be able to do so. The "manage" button in their dashboard will be disabled and will return a page that says "you do not have sufficient privileges to access this page."
This will protect the email addresses and IP addresses from being shown.
There is probably a better way to accomplish this, but it has worked for me and I hope this helps someone.
By the way, you can use the new plugin Role Manager to create new roles and implement the same capabilities.
As far as I can tell, this doesn't affect any other roles.
This is my first attempt at a hack, so forgive me if it's really ugly!