Fantastic idea - i actually thought of this ages ago and wanted to do it myself but i simply don't have time. It would help so much because we could track theories legitimately and then mark them off if they were verified or not.
Could we include rumours within these theories as long as we stated they were rumours, and then mark off if they became verified or ruled out? I mean, as an example, way back when someone posted that a close friend was a hairdresser at a local salon, and that Allison had been there on the Thursday night, most of us felt it was true as it fitted into everything. She stated that Allison had mentioned about the conference and sleepover, and that all of the staff had been interviewed by police, and in the end it all turned out to be correct. People did come up with theories which included those things, and it was helpful.