I currently have the Galaxy Nexus and the Galaxy S2 (with Android 2.3.6). I think that the Galaxy Nexus better: - Feel and weight of the housing (materials and workmanship are excellent, lies perfectly in your hand) - Display (is bigger, brighter and sharper, absolutely inspiring) - Notification LED (very convenient and classy as multicolored) - Google Apps (are clearly modern and efficient (eg GMail or YouTube app)). Unfortunately, however, are a few things for my taste sometimes much worse: - Speakers (quieter and not as powerful), - ICS (a bit "buggy" and inconsistent (menu buttons are sometimes up, sometimes down, sometimes non-existent)), - Position sensor (significantly delayed Screen rotation of about 2 seconds) - Camera (significantly poorer quality of photos, especially in low light). Some apps (eg SN NFL) not or do not function faultlessly (Updates the developer needed). Very inconvenient I find the jack connector on the bottom. Although the camera triggers very quickly, but the autofocus is too slow (hence often blurred images especially in low light). For videos, the autofocus is pumping unfortunately just like the Galaxy S2, so repeatedly blur occurs. The much delayed Screen rotation is not actually on the position sensor, but in the software (probably wanted by Google so; the icons on the camera app, for example, rotate namely delay).
The potential of the device is certainly huge. But the display is even better than the already excellent display of Galaxy S2, especially if you like to look at photos. Google will supply later updates for ICS and the Nexus will certainly be even better if only the weak camera would not.