Digging around a bit more, it's starting to sound like they've been waiting for the Hardware to catch up on this one to do what they want with a full 3D Engine.
Some comments dug up from some Engineers from the previous version (SC4) indicate they were thinking Quad Core or better CPU and much faster Graphics with 1GB-2GB - which they were roughly expecting around 2013 +/- 1 year.
Sounds valid, considering with my FX System the large maps could bog a little on SC4.
Haven't loaded up SC4 with my new system yet.
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