Yes, it would be incompatible. But there could be a mechanism to enable the multi-line mode on a per-table basis. For display and grouping purposes, horizontal lines could still be allowed by adding two consecutive lines:
|-------------------------------------+-----|
|-------------------------------------+-----|


Or another character could be used for the line separator:
|=====================================+=====|


2015-03-05 11:56 GMT-05:00 Tory S. Anderson <torys.anderson@gmail.com>:
>
> Not a bad idea, but this would be incompatible with the existing useof horizontal lines to separate sections and export to visual lines, right?
>
> Skip Collins <skip.collins@gmail.com> writes:
>
> > Here's another suggestion. There could be an optional org table mode
> > in which horizontal lines are used to separate rows:
> >
> > | Lorem ipsum dolor sit amet,         | foo |
> > | consectetur adipiscing elit. Sed    |     |
> > | sit amet luctus sapien. Phasellus   |     |
> > | malesuada, ipsum et hendrerit       |     |
> > | mattis, neque neque sodales risus,  |     |
> > | hendrerit consectetur enim ipsum eu |     |
> > | felis.                              |     |
> > |-------------------------------------+-----|
> > | Vestibulum ante ipsum primis in     | bar |
> > | faucibus orci luctus et ultrices    |     |
> > | posuere cubilia Curae; Nulla dictum |     |
> > | iaculis sodales. Sed elementum      |     |
> > | semper leo, venenatis lacinia odio  |     |
> > | eleifend vitae. Aliquam lectus      |     |
> > | felis, tempor nec lacus ut,         |     |
> > | consequat tincidunt nisl.           |     |
> > |-------------------------------------+-----|
> > | Fusce eu nunc sit amet orci         | baz |
> > | lobortis accumsan. Vivamus laoreet  |     |
> > | ante pellentesque, scelerisque      |     |
> > | tellus nec, ultrices nibh. Etiam    |     |
> > | scelerisque lobortis erat, in       |     |
> > | consectetur nisi tincidunt a. Duis  |     |
> > | eu est elit. Pellentesque fringilla |     |
> > | gravida ligula, non convallis       |     |
> > | ligula viverra sollicitudin.        |     |
> >
> > Perhaps adding the required machinery to allow in-cell paragraph
> > filling would not be too difficult?