The story line has been advanced a bit. The CEF invasion has failed. Earth abandoned several hundred thousand grels as well as contingents of their hover tanks and whatnot on TerraNova. Such forces have formed the "New Coalition" (NuCoal) along with some Badlands independents. Their base of operations is centered at Port Arthur near the equator. As well, there's a PDF army list for the CEF.
The NuCoal army list has Grels, Hovertanks and stuff like that. So between that and the playtest CEF PDF, you can use all your miniatures. If you want to play the original invasion of Terr Nova, taking only Earth Specific stuff out of the Port Arthur list would work fine.
I wanted to add what I can't quite decide is a feature or a bad thing in my little mini review here:
The army lists are not easily accessible/dumbed down. You decide on a TV level (points level), a priority level (how important your force is, what access it has to elite choices which effects your victory conditions) and you also decide on which army you are doing (4 different Northern forces, 5 different Southern, 2 Paxton/Peace River, Leagueless/Independants/Mercenarys, Port Arthur/CEF).
Each one of those armies has different units that count as core, auxillary, elite, special forces, etc.,. For example, the Recon squad of gears is a core choice for Norlight Armed Forces but an Auxillary choice for the other 3 Northern forces.
Your priority level dictates how many auxillary per core, how many special forces, etc.,. So basically you choose a combination of your Army and a Priority Level to get the army list you'll be using. As well, each army has special rules about custom gear choices they can substitute in.
All in all, this has resulted in an army list system that appears to be incredibly flexible to allow you to use the miniatures you want, but it makes it incredibly hard to appreciate the subtlety of choices/upgrades/options for people that don't know the system inside out. I have no idea if it's a good thing to take advantage of the Norlight's ability to substitute Cheetahs for Hunters. From what I gather Hunters are the basic grunt gear that is mass produced while the Cheetah is a more agile scout/recon gear. I guess this means I can make up for the fact that Norlight can't take Recon squads as Core choices by making my general purpose squads full of recon gears (Cheetahs).
As someone who doesn't have a lot of experience with the game, this makes army building quite daunting compared to say, Warhammer 40k's system of "buy an HQ and 2 troops to start, add a fast attack, heavy support and an elite later."
So that's a good thing and a bad thing. Bad in that it'll take a bit of extra thought to figure out what you want to build the type of force you want, but good in that you have tons of options.