Most definitely not gone! PAT is still being actively used. Some earlier posts give an insight to its format but there is little prior preparation available.
Before you ask, yes, I have done it and my experience indicates that it is a mostly interesting and positive day.
Sorry but I won't be listing the questions I was asked during the interview.
The format is: online psychometric test before attending, a personal interview followed by the computer based excersises and finally a debrief. Total time 4hours 30 mins. Each candidate will receive an email, prior to attending indicating the type of computer excersises and an actual flying incident that you will be asked to research and then answer question about during the interview part.
Hope that helps, best not to worry too much about it, if you're invited, just go and do it.