I've yet to see a 3870 at 220.... everyone i've seen is 249.99 at the cheapest up to 269.99. I've seen 8800GTs at 249.99 also. So... They're direct competitors if you find a place that isn't gouging for either.
edit- BTW I'm a pretty big fan of the 3870 with prices going to go down and it having almost equal performance to the 8800GT it's not a buy people should pass up since it's easier to find than the 8800GT.
edit- BTW I'm a pretty big fan of the 3870 with prices going to go down and it having almost equal performance to the 8800GT it's not a buy people should pass up since it's easier to find than the 8800GT.