If Motorola's Brazillian website is to be believed, an LTE version of the 2nd generation Moto G could be on the way soon, and it's packing more than just additional connectivity. According to the specification page, the new LTE G will get a substantially larger 2390mAh battery (versus 2070mAh normally).
There's also a distinct line in the display specifications for the LTE G, but as far as I can tell it's the same 720p IPS panel with Gorilla Glass 3 that the 3G version has.
While this is official confirmation (essentially) of the existence of a new LTE Moto G, it's worth noting that Brazil typically gets Motorola models specifically for that region, so specifications will likely vary a bit if we see this phone stateside or elsewhere in the world. Specifically, you can probably count out the dual SIM capability unless you're in Southeast Asia.
Currently, the 2nd Gen Moto G sells in the US only in 8GB trim, so it seems likely that when and if the LTE version launches here, we'll get the bump to 16GB advertised on the Brazilian phone. Pricing is still up in the air, as Moto's Brazil site doesn't actually allow you to order the LTE G yet, but I'd expect a substantial bump over the standard 3G edition.
Motorola - Thanks, João!