Does Love Wins promote Universalism?
No. Rob isn’t suggesting Universalism [all will be saved, regardless of their faith]. He is proposing that God’s love is so big that the invitation to God’s grace may extend into the next life so that all could be saved. Love Wins clearly points to the centrality of Jesus and the work of his life, death, and resurrection and the hope that Christ’s work will bring restoration to all. Jesus is the only way to God. God’s love does not force anyone and there may be those who continue to reject the invitation extended to them. Love Wins speaks often speaks of human freedom [72-73, 103-104, 113, 115, 117]. Rob shares, “Love demands freedom. It always has, and it always will. We are free to resist, reject, and rebel against God’s ways for us. We can have all the hell we want.” 
Ok, so Rob Bell isn't a universalist if you only define universalism is saying that people are dragged to heaven kicking and screaming (politely "regardless of their faith"). He's not a universalist in the sense that he believes all people are good and Jesus didn't need to die because everybody automatically goes to heaven.
But what about Christian Universalism in the type we see in Gregory MacDonald's The Evangelical Universalist or Thomas Talbott's The Inescapable Love of God. My cursory use of these works has left me asking: what if any is the real difference between this universalism and Bell?
By Rob Bell's standards then Origen wasn't an universalist because he believe the cross reconciled everybody. But any standard discussion of this Christian notion of universalism labels Origen as such. It's a fair term applied in a fair way even with Origen's specifics which differ from 19th century unitarian universalism or some other species.
Rob Bell says he's been slandered (although he does not say where--see imbeded video). Maybe he believes along with Mars Hill that saying Rob Bell is a universalist is "slanderous."
I think it is far more slanderous and abusive to redefine universalism (the large category) to be limited to one sub-species of universalism. Whether intentional or unintentional it is misleading and deceptive to relabel categories. So you try to win a hearing with "I believe in hell" while you are clearly advocating a very different conception of what "hell" means.
If in the end God's redemption accomplishes the winning back of all people even those condemned at the final judgment, then regardless of what you say about Jesus, his death, his saving power, and how and when his "Love Wins" you are still a universalist (albeit a very specific subspecies--but what universalist doesn't belong to a sub-species?). No amount of decrying can change things. A duck is still a duck--even if you're a Merganser but clearly not a common stock Mallard.
I'm not sure why Rob Bell does not just embrace the title "Christian Universalist" in the general category of the works cited above. But then what do I know I'm just a blogger and we live to slander (*sarcasm).
(Even wikipedia gets the differences between types of universalisms and Christian universalism but with clear commonalities. See also Trinitarian Universalism.)