I can give a simple reason for why they didn't announce Jedi sooner: it wasn't ready. We've known for a long while that they only announce features when they're playable and working on the internal servers. That way they aren't just blowing hot air up our skirts. Jedi's finally in a solid state, so they announce it now. I bet all the footage of Jedi on its class page is actual in-game abilities, not just pre-rendered "this is what we want Jedi to do!" bullshot(yes bullshot, look it up).