I think they have had a change of heart.  Instead of doing a bare bone press release (like what Paul Moon indicated earlier), they seem to have decided that the more the merrier when it comes to data transparency. 

Don't know why...but a webcast implies that. 

Also, if they had database lock on Sept 19, then we should not expect anything more than basic top line data. Impossible to do detailed analysis on too many issues (not to mention get them verified by an outside statistical consultant) this quickly.

The only question is whether they will take questions or not.