Thanks that all I needed to know. I thought you could downgrade this was because I was wondering how all the people without Internet will be able to restore or "downgrade" their I4.
Just stroll to a wi-fi hotspot. If it's not a laptop, take it to a friend's house. You could also, in theory, restore it and activate it on another computer with iTunes.
Apple changed the way you do firmware restores/updates etc where now you need to have an internet connection. I think they did this when the 3G came out. With the original iPhone you could just restore and/or upgrade from the file saved on your computer without internet connection. So, if you are on a trip somewhere and wont have access to a computer with internet access/iTunes try not to mess around too much to a point that a restore is needed cuz you'll end up with a brick until you can get to a computer with net access and iTunes.