Nothing yet, but as Sony is a public company, if it were false, a denial would have been out pretty quick to not upset shareholders.
On the other hand, if everyone responded quickly to all allegations they wouldn't be doing anything else in future. So it still looks unfounded to me. I guess if official channels keep ignoring this for longer than say today and tomorrow... then the delay is more likely on. Maybe they are running into problems but they may think that if they work 25/7 they will still make the deadline.
Who knows. It wouldn't be the first game to be delayed, but if its really just a rumour, then the gaming news sites should start thinking about their work methods
