I think it may be *1* contributing factor to early potty learning, but it isn't a given unto itself.
My son was day-trained shortly after his 2nd birthday, and out of even over-night diapers by 2 1/2.
My daughter is home day-trained now, but wears diapers for outings and over-night (she asks to potty when we're out most of the time, but it's sometimes just too far for her yet). She isn't quite 2 yet.
BUT - they've both had full access to a small potty at home from the time they were mobile at all. Both has VERY frequent diaper changes (as in - every time they so much as dribbled some pee). Both had lots of nakey time once they could walk (and had slowed down thier bowel movements
) because cleaning up messes just hasn't been a big deal to me. Both had full access to see both DH and myself using the toilet. Both were set onto a potty whenever mommy went potty as soon as they could sit up unaided (diapered at first, but soon undiapered).
I think there are a LOT of factors to potty learning, regressing, etc. Cloth diapers MAY be one of them, but I cannot see them as a deciding factor.