Which is correct: "standing on line" or "standing in line"?

I'm curious to hear from folks in the the Northeast United States (or anyone, really) an explanation of why "standing on line" seems preferable to "standing in line" in the US northeast.

I imagine for many people that their reasons for preference will be that "It just sounds better," just as my reasons for my preference is that "standing on line" sounds too awkward to my ears. That said, I can't even create a linguistic argument for why it might be more "correct."

There is no linguistic reason why either one is correct. This is a normal example of language variation. There are possibly linguistic reasons why such variation in prepositions is fairly common, that being that the meaning of prepositions in many cases is notoriously hard to pin down (in some cases, they have no real meaning, acting instead as plain case markers).

^{Disclaimer: not exactly a Northeasterners. Like "not at all".}

Standing in line is the most common usage, yet "on line" has been used for some time now.

(This blog post comments:

Many commenters have pointed out that this seems to come up a lot in New York (and New England).
I was just watching 2001: A Space Odyssey by Stanely Kubrick and Arthur C. Clarke, released in 1968. I noticed “on line” being used and looked up and it turns out that Kubrick was born in New York.
So take of that what you will. This also is evidence that it is definitely not a new or recent phrase.

The debate raged on democraticunderground.com:

We say 'standing in line', as in 'in a line', eg. 'part of a line'.
'Waiting FOR you' is waiting for another person to arrive or accomplish something.
'Waiting ON you' happens in a restaurant.

I Stand On Line At The Bank... My Car Gets In Line At Jiffy Lube

So unless you have to walk over and stop on a line in order to wait for your turn, ... you probably are waiting, standing in line.

Standing on line implies that you are standing on something. Since the line is composed of people, isn't it more likely that you are standing in the line, not on it? I think the use of the phrase "on line" as it relates to the internet has become so common, that it may have migrated to being used to describe standing in line.