I did this event last night (fun, nice people) and I was asked about how the press should deal with the DNC leaks.
Anyway, my basic position is that this type of hack(or however the emails were obtained)/leak generally doesn't rise to the level of newsworthy and in the public interest which would in any way justify the means that they were obtained. Sure there are some interesting things, but I haven't seen much that rises above the level of gossip. Anyone taking an absolutist position against obtaining information through nefarious means is taking a position against journalism, really, but that doesn't mean all information just wants to be free and any nefarious means is always justified.
However, they are, as Cokie says, out there. You can't put that toothpaste back in the tube. They're going to be disseminated and seen and spun by crappy news outlets and stupid bloggers and partisan entities which are trying to make a shiny enough soccer ball so that if they kick it the rest of the press will follow. And context really matters for a big data dump of emails. For example, the internal discussions of political campaigns and the relationships between campaign people and reporters is not something people understand very well if they've never done it. Things can easily be painted as somehow "corrupt" and the press can be portrayed as being "complicit" in something when it's actually just perfectly standard behavior. You know, things like journalists contacting a campaign to comment on something can be seen as the journalists coordinating with a campaign or warning them about a story that's coming, when in fact it's just good journalistic practice.
So even if the stuff in the leaks isn't really newsworthy, journalists who do understand this stuff should take a look at it and provide the proper explanation and context. There's a big history of portraying perfectly normal political actions by the Clintons as somehow being deviant and corrupt, when they're just standard operating procedures. They're just what everybody does. Things like "campaign tries to forge good relations with members of the press" or "campaign plots strategy months in advance" are normal. Maybe some of it's gross, maybe normal is gross, but it doesn't say anything specific about the Clinton campaign other than they're playing the game as it is played.
tl;dr: can't ignore the leaks, this is an area political journalists should have knowledge of and expertise in, so they should use that to explain them.