Unfortunately, other than a post from Lhivera, I can't get anything definitive. He says LB is better for single target, but my main beef with LB is that realppm procs make up a huge part of our DPS right now and I don't think he's taking that into account. Assuming the periodic is the same, the explosion damage is "a bonus" on single target, but I think that bonus might get negated by less trinket/metagem/jade spirit procs.
A metagem or Time Warp-hasted NT ticks 20 times versus 7 for Living Bomb. That's a pretty big disparity. That might very well make NT still better.
If anyone thinks LB is better on single target, I'd love to hear from you here or on that thread. Otherwise I'm planning on checking my uptimes on logs in 5.3. Thanks.
Disclaimer: I'm not a huge math buff so I'm not necessarily saying one is better than the other, just looking for input.