I'm more of the "sin boldly, but believe and rejoice in Christ even more boldly" crowd.
Regarding the 2nd paragraph, is Warren trying to say that Christianity isn't a religion? Or is this a way of "elevating" Christianity above all other religions? Is he saying Christianity is more than a mere religion, it's the only "right" way for anyone to be in a relationship with god?
The quote used in the 1st paragraph seems to be a bit out of context, and I find it interesting that he chose the C.E.V. for this one. The book reminds me of some of the pop psychology of the 70's. It's geared toward the personal growth of the individual, while many of the Bible quotes were addressing the growth and well-being of the community. I realize he uses various translations throughout the book. Anyway, the quote is from Romans 15:2 ---
http://www.biblegateway.com/passage/?search=Romans%2015&version=CEVRomans 15 (Contemporary English Version)
Please Others and Not Yourself
1If our faith is strong, we should be patient with the Lord's followers whose faith is weak. We should try to please them instead of ourselves. 2We should think of their good and try to help them by doing what pleases them. 3Even Christ did not try to please himself. But as the Scriptures say, "The people who insulted you also insulted me." 4And the Scriptures were written to teach and encourage us by giving us hope. 5God is the one who makes us patient and cheerful. I pray that he will help you live at peace with each other, as you follow Christ. 6Then all of you together will praise God, the Father of our Lord Jesus Christ.
The focus on community seemed to get lost in Warren's application.
When Warren does manage to address community, it's focused on the fellowship of believers. He pretty much ignores the wider application of a sense of community with all humankind - with all of creation. Not much about loving what God loves or even trying to discern what that might be.
I have the book, it was a gift from one of my nieces. But, I never got into it. I couldn't get past the "you were put here to prepare for eternity" message of his 3rd chapter.
That's just me though. I had some pretty bad "born again" church experiences early in my life so that whole "decisional, evangelical theology" tends to give me the creeps (as does Warren). I'm working on overcoming those prejudices I still hold from my past. Anyway, he does have some gems in there and if it motivates you or (better yet) draws you closer to God that's great! It just doesn't resonate with me at all.