Arrgh, also have the same problem now...... NO KEYBOARD.
Note this seems to be a common bug...
Introducing: Better Keyboard for Android Better Android Apps
I have just fixed it though by doing the following.
1 reboot (didnt seem to help)
2 Settings->Locale & text, selected Samsung Keyboard (guessing this may be the KEY step here)
3 Didnt change anything, pressed back
4 Select Locale, Select English(UK)
and it seemed to come back, although now looks quite different from what we had before.....