After the resignation
BBC News: Charles Allen quits as ITV chief
MediaGuardian: 'ITV needs content king'
It's still uncertain who will properly replace Charles Allen, let alone whether ITV plc will survive until then without succumbing to a hostile takeover (all eyes will be on that share price). Channel 4's Andy Duncan looks to be a very strong candidate but he's unlikely to accept what's likely to be a place on board the great ship Titanic (unless someone can move the iceberg).
The big mystery surrounding Charles Allen's tenure at ITV plc concerns his failure to address the issue of contract rights renewal (CRR for short), which basically speaking pegs ITV's ad revenues to ITV's market share. So when ITV's share of viewers drops - as would be expected with greater commercial competition - its income drops proportionately as a result.
Presumably CRR was adopted because it was seen at the time to be the only solution that would permit a Granada-Carlton merger, but as time goes on this looks to be like yet another foolish decision - maybe Charles Allen was reluctant to backtrack on something that he had a hand in negotiating?