Surprisingly, no... they don't seem to have any intention of modernizing the game in this way. I'd
love nothing more than for them to prove me wrong on that though.
But there's good news if you're interested in 64bit Terraria and haven't heard -- there is an incredible project that successfully allows for 64bit Terraria to work
flawlessly. It's mainly for those heavily into modding the game. If you're into using large mods or many mods, I
thoroughly recommend it:
Standalone - [1.3] tModLoader FNA (32bit/64bit) (Branch of tML)
We're blessed to have such dedicated and
amazingly-talented people in Terraria's modding community.