You can't currently use Runeforging on Heirloom weaponry, no. You can only use enchants with no minimum level requirement on Heirloom items, and any enchantment that would make the item soulbound is a no-go as well. If you like keeping top-end enchants on your weapons at all times, an Heirloom weapon isn't the way to go.
I remember hearing that they were working on a way to let Runeforging work on them at the very least, but I can't honestly tell you if that's true or not. I couldn't find a quote in my grueling 5 minutes of searching, so let's just go with a 'maybe' here until I can find it.
"Pandaren. Chinese/Panda violence rumor. Kill it for me. Use facts. I know I know it gets asked a million times. But please kill it again."
It's true that China isn't down with Pandaren, but I don't know if it's due to violence or some other panda-related thing. I believed it was false for a long time, but it's unfortunately at least somewhat true. There aren't many facts I can cite, but I can point to what J. Allen Brack said at BlizzCon 08. Just check out our liveblog of the WoW Q&A Panel, the answer is in there. As you said, this gets asked a million times, so I won't go into heavy detail here. China's censorship board is harsh, and I'll leave that there.
"What's the lore behind the Argent Tournament? Granted, I'm not on the PTR, but right now it seems to be just some random thing Blizzard tossed in to keep people interested. I mean, the Argent Crusade must have their hands full with the Lich King, so is it really that prudent to be throwing a big party in the heart of his kingdom?"
It's hardly a party. They're war games, blood sport, a promise of glory to all able-bodied fighters. It's a disguised recruitment drive, in other words. They're attracting more fighters to their cause in Icecrown, and using the tournament to weed out those that would just get themselves undeadified on the battlefield. It's also something of a 'screw you Lich King' move, because they're building this awesome colosseum right on the Scourge's front yard, which is a huge boost to morale.
"I'm wanting to be able to finally communicate on vent since I'll soon be tanking raids. What affordable (< $30) mic does the WoW Insider staff/community recommend?"
You can get a decent headset for under $30 pretty easily. Logitech or Dynex have some decent, cheap ones. Just head over to any old Best Buy (or even a place like Target) and look at what they have. You don't need to be too picky, just look for something that will sit comfortably on your ears and doesn't seem like it will break if you accidentally drop them once or twice.
I have giant Dumbo ears so I tend to look for comfort as my primary headset requirement, so any specifical models I could suggest may not be something that fits you very well.
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