No. Blizzard is going to keep World of Warcraft going as long as it's profitable. Why would they arbitrarily end (one of) the most popular MMO(s) in the world? Even if they released their new MMO before the end of Cataclysm's life cycle, ending WoW would be foolish and probably one of the worst business decisions they could possibly make.
"Will we be able to fly over all of the old world content, or only over the capital cities?"
There might be specific places Blizzard won't allow us to fly, but for the most part all old world content will be fair game. They're filling in all of the little eyesore gaps in the terrain, they're sprucing up the empty areas and filling in all of the zones that weren't implemented yet such as Hyjal. You should be able to fly from Booty Bay to Light's Hope Chapel with no issues whatsoever.
When it comes to places like Exodar and Silvermoon City, you'll probably still need to fly through an instance portal or take more mundane methods of travel such as a boat or a flight path. Those places are on different world servers than the "old world" of Azeroth, so flying straight to them isn't a viable option. You need the instance portal, rather than loading screens where a player can pop into some random spot in the zone all of the time.
"Ghostcrawler gave us a pony and it sparkled. Will our moose sparkle too?"
No. It will be covered in spikes. It will impale dragons on its mighty antlers, much like the spires in Blade's Edge Mountains. Sparklepony can only be defeated by spikemoose.
"Leveling in Cataclysm: Raid gear or heirloom gear?"
They've mentioned that current heirloom items won't scale to level 85. You won't get the XP bonus from them, so there's really no good reason to use them unless they're better than any other level 80 gear you have. Considering the question though, I assume you have pretty good raid gear. Use that for leveling.
Hundreds of people asked:
"Why haven't you guys posted about that Norwegian kid that feign death'd a moose?"
We did. Three years ago.
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