Outfront II is actually the sequel to Soldiers: Heroes of World War II, which was originally known as Outfront. The well-received original is going to see a minor graphical facelift to the graphics engine, but the focus will be mostly on gameplay features.
Outfront, unlike WW2RTS, focuses more on squad tactics than the larger scale company battles. Thus, most of the improvements have been aimed at making infantry combat more interesting. Most of the work seems to have been spent on improving the AI of the units. Outfront doesn't force the player to find cover for his men individually after ordering them to move - they do it by themselves. They react intelligently to threats and respond appropriately. The player can adjust their individual courses of action, like ordering them to pick up an enemy's weapon or to steal a tank.
Vehicles are quite prominent in Outfront and the game makes allowances for crew skill and numbers. Taking over a tank with less than the optimal number of crew will result in reduced performance, but not just in a generic way. A single crew member can drive the tank, and if needed, he can switch to the loader position to load a shot, then to the gunner's seat and fire it, and can move back to the driver's spot to drive again. All this is simulated in the game engine - as is his abandonment of the vehicle if it's damaged, assuming he survives.
The smaller, more intimate scale of battle than in World War II RTS allows soldiers to swap equipment between each other and from fallen foes. An enemy's helmet may be picked up, and it will show on the character, as will different types and numbers of grenades on his belt. Thanks to the new physics system, the environment reacts appropriately as well. Pistol shots may not punch through a fence but a rifle will, while a flamethrower will light it on fire and a grenade demolish it entirely. Vehicles and buildings are destroyed in a convincing fashion, walls collapsing, turrets popping off and engines flaming. Crew can even catch fire while inside a vehicle and escape only to continue burning to death on the outside. This is a highly realistic if somewhat macabre touch - death by fire was the most common way for tankers to perish then and remains so now.
Outfront uses an interesting art style that isn't completely realistic but isn't aiming for a cartoonish impression. Rather, the somewhat flatter color palette resembles illustrations of vehicles and uniforms that are used by modelers and history buffs. The effect isn't impressive in the Unreal 3 way, but feels very appropriate to the game.
If you're interested in either World War II RTS or Outfront, we'd also recommend you also investigate Blitzkrieg II from CDV.