For a certain demographic, a new modern Battlefield game with the Frostbite engine, and today's graphics - but set in the WWII era - could be phenomenally cool. And by certain demographic, I mean people who are either history buffs, or in general older than the typical raised-on-COD crowd. I throw myself into this group...
I first played Battlefield 1942 back in 2005 or so... for about a week, until the Battlefield 2 beta came out, and I was hooked. I did detour into Battlefield Vietnam, which seemed to me just a Vietnam-themed variant of 1942 - but still a great game. Easily the Best Soundtrack ever, for any COD or BF game!
I was always surprised that the BF Bad Company 2 variant Vietnam didn't do that well - it was a great game, built on the BFBC2 platform, but with Vietnam-era weapons, including a flame thrower. Great fun. Plus another cool late 60's sound track!
I've also played COD World at War, which was out - don't feel like Googling at the moment - around 2008 or so? It was an awesome game, both single and multiplayer - but it was quickly forgotten as COD went into the Modern Warfare areas. A really cool WWII-era game, with cool guns from the period, etc.
I personally would love to see either an EA-produced WWII-themed game, or at least a modern engine that is moddable. I miss the days of BF2, with its Point of Existence (POE) and Project Reality (PR) mods. I'm pretty sure there was a BF2 WWII-themed mod, but I can't recall the name.
With BF4 seeming to encroach on the new/old technology that was popular in BF2172... Will EA return to WWII? I'd love to see their marketing data on that question too!