In close, a handful of observations on the last third of this interview...
Warren doesn’t really answer the problem of those who have never heard. Instead, he very quickly moves to the topic of getting missions out so those people can be saved.
I was pleased to hear that at Saddleback, they have some depth studies, including a 72 week systematic theology course. However, the content of Warren's writings (like PDL) leave me wondering what exactly he considers to be "depth". Further on he makes disparaging remarks to the effect that making Bible study deep doesn't mean explaining the background, it means transforming the student (!), and implies the former is "muddying" and making Scripture more complex than it needs to be. In a nutshell this is a doctrine of radical perspicuity, and it is harmful in the long run. Depth Bible study should be both transforming and background-explaining; if it is not, the transforming will head in the wrong direction, or be without adequate epistemic support. I fear that, in a manner similar to leaders in the emergent church and many pastors, Warren thinks that if a believer has "passion" that it will be a fuel to sustain them. Well, if they are emotional personality types -- as Warren evidently is -- it might. But that's only serving the extroverted part of the population. In that light it's somewhat tragically ironic that Piper asks Warren to leave a legacy of depth by training pastors. I can only hope that he either doesn't, or that he at least assembles a team that includes Biblical scholars if he does so.
In sum: Warren is revealed as a generous (he is a reverse tither) and humble man on a heartfelt mission, but also someone who is, in certain unfortunate critical aspects, clueless -- which is the same impression I got reading PDL years ago.