Welcome aBoard, Mike--glad to have you! I've sent off to Brandon, our resident ASL expert (literally); with luck, he'll chime in with some enlightenment. Dr. Bill expressed perfectly how I feel about this word, which I had not heard before: At first I thought the coinage clumsy, but on second thought, I'm surprised ;it didn't
happen a long time ago. Meetings do, after all, get moved up all the time--someone has to go out of town, or the disaster is arriving sooner than expected, etc.

Here's the "entomology" (remember, tsuwm?) from a person on the site Sparteye gave:
Topic: 5) Move it up (11 of 11), Read 36 times
Conf: Word Fugitives, with Barbara Wallraff
From: Dorothy Glantz (dml.glantz@swipnet.se)
Date: Saturday, November 20, 1999 06:28 AM

The word 'prepone' is found in The New Oxford Dictionary of English, published 1998. It is listed as being Indian (from India) and is defined as: to bring forward to an earlier date or time. Example given: The publication date has been preponed from July to June. Surprisingly, its origin according to New Oxford is the 1970's!
Um--if it is bad form to quote from one word site on another one, would someone please let me know asap, and I'll delete?