The ICS keyboard should work on all Android devices running Gingerbread. I have tested it on Samsung Galaxy S and the Samsung Galaxy S II. The ICS keyboard is actually similar to the one found on stock version of Android 2.3.
Other than that the space bar is now made longer, they have done this by removing the key between "?123" and "," this key was used to select the input method, a welcome change in my opinion!
To change keyboard all you need to do is long press in the text box you will get a pop up on your screen.
It requires the following permissions:
You can download the APK from either,
Source: OMGDROID, REDDIT