I have an 8ms monitor, and I get minor ghosting. Looks like text and details get blurred a bit.
It's something I can't get used to when gaming, but it's not really that bad either.
It has to do with how LCDs and eyes work, even with a ridiculously low time you'll see ghosting anyways since your eyes are actually at fault.
Apparently some monitors have a feature to work around human eye deficiencies:
BenQ's New AMA Z LCD Monitor - No more ghosting and blurring - Softpedia
Also, I wouldn't touch widescreens with a 10 foot pole. The whole concept is vile and resulting in P2P being polluted with cropped videos. =(
Jam it back in, in the dark.