Eavesdropping is at the core of much journalism.
News of the World hacked phones and made no real secret of it at the time. Well its just a four digit code, hardly the way you'd protect anything precious.
Manipulating peoples messages (like deleting old ones to make more room) is a bit different but even so, it was only to make space for new messages, nothing malicious.
At the time, the News of the World even reported specific messages that they had hacked! it would be obvious to anyone at the time what they were doing - no one saw it as a big deal.
However, payments to police for information are a different matter... But there again, News of the World made no big secret of that, retaining emails detailing the payments.
Why has all this other information come out of News International now? is it the other side of a 'deal' - Police and Politicians haven't protected News International so they are being taken down too?
The other question is whether the police/news international information flow was all one way? Or did news international pass information from illegally hacked messages to the police? And if they did was it used for any prosecution?
If people have been convicted on the basis of police evidence that originated from illegal phone hacking, then I think we can expect a batch of appeals from those convicted on illegally gathered evidence.
ps. I'll single out the dreadful Hugh Grant for a kicking - he sold his soul to the public for his millions - he can't expect privacy, and jumping on the shroud tails of a murdered young girl to advance his own cause is digusting.