Possible LOST spoiler?

From io9:

There's a new press release for the final episode, which mostly just summarizes what's already happened. But this paragraph, summarizing the season so far, is interesting:

The final season has also introduced the concept of flash-sideways, portraying two parallel universes. The scenes on the island depict a universe where the bomb failed to detonate and the survivors remained, whereas the flash-sideways show a world where Oceanic 815 landed and the passengers never ended up living together. However, destiny appears to be drawing them together regardless as their lives end up colliding despite the reversal of history. Indeed, following a recent meeting with Charlie (Dominic Monaghan), Desmond (Henry Ian Cusick) starts to feel as if he has led another life before and plans to ‘awaken' the other passengers on Oceanic 815 – starting with crashing his car into Locke as he crosses the road.

Our first confirmation that the two universes are divided by whether the bomb went off? (I mean, it seemed sort of obvious, but it's never been stated.)