New features that will radically increase the playability are: automatization of many functions, such as production and diplomacy, as well as managing armies at different levels, for example at the HQ level, sparing oneself of having to move every single unit.
HOI 3 is, like its predecessors, the ultimate WWII simulation, of unprecedented depth of detail.
Only disadvantages (for some) are that: 1) It's in real time, not turn based and 2) There are no limited scenarios, such as only the Pacific War (or maybe that is going to change in version 3?).
