yes.. you can try to take it back...so that you can get the update. Most likely that is the last OFFICIAL update for that phone.
or.. keep it rooted.. so that you can keep get new updates from the Development Community. This is called "flashing ROM". New ROMs are always coming out. if you are interested, read a little more on the subject. also rooted phones have other benefits as well.
DropBox: register for free space (we both get 500MB extra space): http://db.tt/sWYVl3j6