First of all for those of you who will doubt this; yes, the photo is 100% legitimate, not a "no-name source" sort of deal.
You can check for yourself if you own Burnout Paradise. Simply pause the game at any point, select the "Paradise City Online" menu, and press Triangle. Bam, there's your friends list, just as you remember it from the XMB. You can send and receive messages, change your comment, add, block, remove... anything you could normally find listed under the Friends icon can be found here. Although a few other titles have allowed messaging from certain menus, this is the first time it's been available during gameplay.
While this isn't exactly the full implementation that we've all been waiting for Sony to bring us, it's certainly a step in the right direction, and closer than we've come from a non-PSN title to in-game XMB yet.