Forget Worgen Freeman, I'm rolling a stab-stab-stab rogue named Dexter Worgen. Props to Joker for putting this idea in my head.
"I know there is another patch before Cataclysm. Why isn't anyone talking about it? Are they going to do something cool and event-y like the Scourge infection before Wrath? Maybe some more heavier seismic activity or something?"
There will be another patch, likely numbered 4.0 or 4.0.2. It's going to contain things like the aftermath Operation: Gnomeregan. The only reason you haven't heard anything about it lately is that the patch itself isn't out on the PTR and we haven't really heard much about that patch in particular. Remember though, the "Cataclysm patch" as it will be called, is just a complete dump of everything that's in the Cataclysm expansion into the current world. So all the articles you see about specs and new spells (level 80 and below), will apply to that patch as much as they apply to the new expansion.
"What I am still wondering about is: Why do the hunter trainers in Stormwind and Gilneas still use mana when all the other hunters in game switched to focus?"
Likely because Blizzard hasn't coded over the hunter NPCs in game to be a physical NPC class versus a mana-using NPC class. It might never change, to be honest; I'm sure it's very low on their list of things to get done.
"With gems changing in color come Cataclysm, will we have to replace all our currently equipped gems or will they switch automatically?"
WoW.com reader Cephas gave an excellent answer to this:
Professions are still being worked on, so this might end up changing, but as of the current beta build, BC/Wrath gems have not had their colors changed. Rigid King's Amber is still a yellow gem and it still provides hit. A look into the game files reveals gems like Rigid Ocean Sapphire which are blue and carry hit, but it's possible that these color changes will only apply to Cataclysm gems and existing gems will not have their colors retroactively changed.
On a related note, your ArP gems will automatically be converted to crit gems, which means that if you were matching red sockets with ArP gems, they won't be matching anymore. This is only happening for ArP, i.e., existing AP gems will still grant AP; there just won't be any new AP gems in Cataclysm.
"Any idea if Tol Barad will have its own raid instance, like WG?"
Yes, it's called Baradin Hold.
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