Rob Bell is an interesting thinker. I was exposed to him via his Nooma videos at one of the churches I went to in Lexington. He seemed to be a bit of a free-thinker, but grounded in biblical history, bringing quite a bit of knowledge of first-century historical background to bear on the Gospels.
Thus, his move towards an universalist take on salvation in his new book Love Wins comes as a bit of a head-scratcher; here's a good Timothy Dalrymple piece on "Hellgate."
Good theology starts with what we call exegesis, what the writer or speaker was trying to say at the time; that goes beyond the direct quote and tries to get at what the readers/listeners of the day would have read into it and what was likely intended. Since Bell seems to have some solid exegetical chops, it's surprising that he falls flat here.
As I understand the debate, Bell's main issue is whether Hell is truly eternal or just long-term. The Greek word in question can be used in both ways, but since the "eternal life" in John 3:16 uses that word (as Tim Challies points out), using an eternal eternal for Heaven and a merely long-term "eternal" for Hell seems to be a bit off.
Translation can cause theology to go off the rails; TD Jakes' take on the Trinity as three manifestations (rather than persons) seems to flow from the King James Bible's use of the word. By questioning the translation of "eternal", Bell alters basic orthodox theology by bringing a small-u universalist desired hermeneutic and warping the exegesis.
It is the Reformed Blogosphere that lit up first, since universalism throws TULIP out the window; or at least ULIP, since we can be Totally Depraved all we want in a universalist worldview, given that God's going to save us no matter what. The more Arminian side of the aisle were as inclined to criticize the Reformers than to defend Bell.
One of the harder points of Reformed theology to swallow is the idea that some folks aren't going to be saved no matter what. That leads a lot of folks into the Arminian camp, even if they won't call themselves that; for one example, Baptists often are leery of "Calvinism" on the grounds of wanting a fighting shot at saving everyone they can and don't want Limited Atonement to dampen their evangelism. Save that, there would be a lot more common ground between the neuvo-Reformed and other conservative evangelicals.
Once you open up the prospect of saving everyone, it's not a big jump to question why a good God will let some folks roast in Hell and some not; that might explain the lack of fire coming from non-Reformed circles. Once Heaven becomes an open set, what is there to keep it from become the entirity other than harsh theology?
An emphasis on free will might be one. If God prizes a free choice from His people rather than a forced response to follow Him in Reformed thought, might an Arminian God opt to accept the decision to turn one's back on Him? Or does He drag Christopher Hitchens kicking and screaming into Heaven?
Rob Bell seems to think so. Interesting. Likely wrong, but interesting.
One of the downsides of being a free-thinker is that you tend to ignore traditional viewpoints. If tradition seems off, you go your own way, not thinking that it might well be that you're the one that is off.
Traditionally, eternity means eternity, not a 99-year-lease that rounds to eternity in financial math but will expire someday. Ignore that idea at your own peril.