What's this? An official Samsung ROM with the most desirable bit of software this holiday season? Someone out there has been a very god little Android modder this year, and if you own the international version of the Galaxy S II, you can take advantage of his or her good fortune. Sammobile got their ans on a leaked version of Ice Cream Sandwich for the SGSII, and the adventurous can flash it at their leisure.
The ROM is a customized version of Ice Cream Sandwich that's a long way from ready for an OTA release, but it's surprisingly complete for a test build. All the basics are covered, including calls, SMS, Internet access, etc. Sammobile claims that some of the apps are unstable, and random reboots are an unfortunate reality at this stage. By all accounts, it isn't ready for use as a daily driver.
The implications for the modding community are good: even if the OS itself isn't fully baked, the modified Ice Cream Sandwich kernel should allow quick and easy builds from AOSP's open source code. With any luck, basically complete custom ROMs could be ready well before the end of the year. As always when flashing new ROMs, remember to keep a Nandroid backup close at hand, and be prepared to be a literal test case for Samsung. You can find the download at the source link. Be aware, it's not your typical CWM flash- this one will require a little more finesse using Samsung's ODIN.
UPDATE: Sammobile posted a video of the ROM running on the Galaxy S II. Enjoy!