I had ordered the 3G one, but just cancelled and went for the wifi only as Im mostly at home with it.
Having read the manual, it seems as if it uses wifi as standard and the 3G is really just a backup, so seems pointless in my case, not sure I'll ever use the 3G.
The £40 saving is best used for new ebooks and the extra battery life seems to outweigh the pros of 3G for me
So I ordered the graphite wifi and the apple green lighted cover
but then I keep swaying between wifi and 3G, just not sure........the battery life using wireless is so different, 10 days/3G or 3 weeks/wifi, thats the thing that bugging me......just can't decide on one and be happy