Electronic Arts today announced the “epic conclusion” of its Tiberium real-time strategy series with Command & Conquer 4 for the PC, slated to ship in 2010. EA says the game, which is being developed at Electronic Arts Los Angeles, will build on the franchise’s core mechanics by adding class-based gameplay and mobile bases, and also promises player progression that persists across all the game’s modes. The conclusion of the seminal RTS series, which was originally …