I would say that 72 points would be enough, which is 1.8 points a game from here on in.
I mentioned on another thread the important of an experienced spine, and in the 21 games, where both Mous and Henry have played, we have picked up 1.85 points per game (from 21 played).
So 72 points is certainly doable, especially as 60% of our games are at home. I know anything can happen, but you would fancy wins against Wimbledon, Accrington, Southend, MK Dons, Tranmere and Bolton which would leave 9 games where we would need to average a point to get to 72. That should be enough, especially if we don't lose any of the games against the teams around us (Sunderland, Ipswich, Cov, Pompey and Wycombe).
That's why I'm not getting some of the "mid table mediocrity" rubbish. This season is still very much there for the taking, especially if we finish strong when others start slipping back.