We already know that Android 4.2 Jelly Bean upgrade will be the last major update for the Samsung Galaxy S II and Galaxy S II smartphones. But the good news is the wait is almost over and Samsung might soon start seeding the Android 4.2 Jelly Bean update for the Galaxy S II Plus. What's more an official (if probably not final) ROM has been leaked and if you are really impatient you can flash it...
Source: http://www.gsmarena.com/official_android_422_update_for_galaxy_s_ii_plus_leaks-news-6505.php