Has not yet begun to fly all the ROMs for Samsung Galaxy SII scene, and even We are still awaiting that great teams like Cyanogen and MIUI begin to develop officially for the new flagship of Samsung.
Even so, a group of external developers at xda-developers have begun to Porting the famous MIUI for the elder brother of the Galaxy, and although still have the development at alpha stage, We already have a video where we can see a Galaxy SII running MIUI.
For the time being It is not recommended to install this ROM, and is giving many problems related to the recognition of some features and sensors of the terminal, but is available for download If someone wants to try it.
Then you have the video sample:
View the video at the original site.