Found this plug-in that may allow you to connect to PMS from within XBMC on your ATV 2. I installed it on my iPhone through iFile and once I logged in to my Plex account, I can see my folders. Too bad I’m not at home and my Mac is shut down. Cannot confirm it actually works, but installing an addons from a zip to the ATV looks like a painful process. May try it out when I get back home.
Here is an image of the plug-in
I was able to get this installed on my Apple TV 1 (with aTVFlash Silver) by doing the PleXBMC install via ZIP file. There were a couple tricks along the way, but here is how I did it.
Download the appropriate pleXBMC add-on for your version of XMBC on your AppleTV (11.0/Eden in my case), http://wiki.xbmc.org/index.php?title=Add-on:PleXBMC
Transfer the ZIP file you downloaded to the Apple TV. I used FTP from my Mac to copy the ‘plugin.video.plexbmc-v2.1.zip’ file over to the Documents folder on the AppleTV, http://support.firecore.com/entries/259290-Transferring-Files-via-FTP
Then I launched XBMC on the Apple TV and followed the ZIP add-on install proceedure from the XBMC online manual, http://wiki.xbmc.org/index.php?title=HOW-TO:Install_an_Add-on_from_a_zip_file. I found the ZIP file I had transferred in steo 2 on /Home/Documents on the Apple TV
Once installed I was able to go to Videos > Add-on in the XBMC interface and access pleXBMC.
Now the tricky part. I couldn’t figure out how to access the settings. It seems to try and come up on first launch, but closes immediately. To access it, on the Videos > Add-ons screen, with pleXMBC selected, press and hold the menu button on your remote. That will bring up the settings. Then you can go in and configure the pleXMBC client to set Bonjour discovery and add in your myPlex username and password. Once that is done then you should be able to see and access your Plex Server.
I was finally able to get this plug in on my ATV 2 by adding the superrepo. Went in like u said and changed bonjour and signed into my plex account. Still no go. Screen goes black, and ATV goes back to homescreen : (