There's either a daily or NPC that mentions that the Firelands is to the east of the Molten Front. I'm pretty sure it's a NPC hanging out with the Shadow Wardens. He says something about Beth'tilac being over to the east. If you go to the edge of the zone you can see another island that is likely the Firelands.

They actually are connected, just not by the map.

If you do the bombing run daily for the Druids ('Fires in the Skies' I think it's called), you end up flying to the South-East of the Molten Front, over that floating volcano that sits behind the portal, and out into Beth'Thilac's Lair, where the bombing run takes place.

So technically, the Molten Front is to the West of Sulfuron Keep, and not shabby a spot to plant a sentinel tree, as it's essentially right in Rag's neighbour's yard.

You don't even have to go to the East. Just -look- East. That huge mass of floating rocks with Sulfuron Spire at the other end of it? That's the Firelands raid zone. They hover right next to each other in the fiery void.

Heck, if you have far-sight (either hunter or shaman version) you can chain cast it to explore the Firelands from the molten front. If you get to the bottom of the path leading up to Beth'tilac's lair, Blizzard tossed in something extra for you.

They are definitely connected. When you sign up to help the Druids of the Talon, one of your potential quests is a bombing run of the Firelands raid. Yeah, you actually fly over in one smooth transition and bomb a bunch of spiders and flamewalkers in and around Beth'tilac's lair. Lore-wise then, the Molten Front dailies are where we start the attack on the Firelands before we actually send in our heroes to kill the big bad lieutenants.

"2 really quite small elemental islands in what can only be an infinitely huge elemental plane."

First off, do we know it's infinitely huge? Secondly, even if it is...our real life universe is also infinitely huge, but the parts we can actually change in ways that affect us is, in comparison, a speck of dust.

Really, though, we're attacking some specific elementals, not an entire plane of existence. Consider us to be Raid Team 6, strategically dropping in to take out Ragnarosama, and you're wondering why that matters when there's still all of Pakistan around him. ;)

SS or it didn't happen, cutaia.

@Cutaia, why don't you come back and try that with 24 of your friends?

Something else i havent seen anyone mention, on the bombing run quest, in one corner... theres a raid group. If you fly close enough you can see their text sometimes, theres a bear tank jumping around saying "can i pull" over and over or complaining about someone being afk.

Just looked em up.

http://www.wowhead.com/search?q=Thrall's+Thrashers
http://www.wowhead.com/search?q=Wrynn's+Raiders

So, I joined my guild in raiding the Firelands last night. I asked a noobish question.

"So when do we get to go in the buildings to kill the bosses?"

Apparently they're just a facade.