Facebook and Twitter login
You can now log in using your Facebook or Twitter account if you wish. To enable this, simply go to Your Settings -> Profile -> Manage Facebook Connect / Manage Twitter Connect. You will have to authorize our application so it can establish the necessary link between your social network profile and your forum profile here. Once that's done, you have some extra settings you can play with, such as updating your forum status with your Facebook status or importing your profile picture.
Note for the privacy-concerned: This is 100% voluntary. If you're not comfortable linking accounts, simply don't enable it and nobody will ever be able to make a connection.
Private Messages
Many user groups weren't able to use the new PM invitation feature that allowed the handy group conversations (think of it as a private forum topic), a core improvement of IPB 3. From now on, users of all groups can issue up to 50 invitations per conversation.
The maximum number of storable messages has also been greatly increased (100 for New Members, 500 for Posting Members and Project Team, 1000 for Hosted). That should make sure you never run out of message space
Reputation
You might have noticed the
and 
icons at the bottom right of every post. Those allow you to give reputation points, which will then reflect in the other user's profile. Give a plus if you thought the post was constructive/helpful/funny and a minus if it was bad (duh). New Members are not able to give any reputation points, Posting Members are only able to give 5 positive reputation points a day and all others simply have some other limits on the amount of points they can issue per day.
