It seems Samsung is rolling out Android 2.2.1 update for Galaxy S smartphones in some regions. While the exact geographical distribution is unavailable now, Nordic countries have at least got it.
The update has made Galaxy S a lot snappier and includes various bug fixes. We will soon be posting the final changelog of the update. Till then try updating your phone via Samsung Kies and let us know in comments if you got the update.
A few twitter users are also reporting getting the update.