As mentioned earlier I play Burning Crusade (BC), the expansion of World of Warcraft, since alpha. I play it with mixed feelings, not only because I have to do it all over again when it launches (all my data will be erased), but because I feel it has design flaws.
An expansion should expand the universe it needs to tie into the existing world. It needs to expand on concepts which where successful in the first one. Currently when I play BC I have the feeling of playing 2 games in one, separated, not even joined.
It starts with the fact that you have to enter BC through a Dark Portal. You are being teleported to it. It continues on the world map: while the two contents where visible on the map and a click apart the new one appears as a separate entitiy outside of the old continents.
And my feeling of separation continues with the details. Let me give one example. If you need resources for your skill (enchanting as an example) you need resources found by disenchanting stuff of the level of the enchantment. No biggy here. In BC you do the same, but if you skill over 300 the "old" reagents you needed are forgotten. You expect you might use the high reagents like nexus crystals for at least some enchantments, but you don't. Its like a cut. Over the skill of 300 you need new ones ONLY found in BC.
What about the guilds who saved their valuable nexus for their enchantments they desparately need to beat the instances? They are now placed like in the middle of nowhere. The effects are already being felt in the old world: nexus prices dropped from like 25g+ down to 15g in the past 2 weeks. They won't be needed anymore as the new enchants are of course better.
Lets take a look at mining. You mine ore and smelt them to metal bars. Many skills need those rare metals to build fantastic weapons and armor. So I expected that the most sought after bars "Elementium bar" will be used for some high end items in BC.
But no. You don't need them at all. You only need rare metals found - you guessed it - in BC exclusively. In case you don't know: to smelt elementium bars you have to gather 10 arkane crystals (another item whic BC doesn't need at all) and smelt the elementium ore -which you can only find as an epic drop inside the Black Wing Lair. On top of that you only learn to smelt elementium by mind controlling a gnome inside BWL. My raid guild collected a lot of these to prepare to build the super powerful weapons.
The whole design of the dependencies was awesome in WoW. If you wear such a sword of power you are a hero. You worked for it, a raid guild worked very hard for it.
When BC comes the awesome weapon becomes a worthless toothpick. Your elementium ore becomes worthless, already dropping in price form 500g down to 120g, and no one wants it.
Why did Blizzard do this? Why at least could some rare materials not being used for BC items? Elementium Ore/Bars, nexus and arcane crystals, all worthless soon? The wealth we worked for so hard is now beaten to death by BC. Is that fair? No it isn't.
Of course there are exceptions, and VERY bad ones too. Dreamfoil is the most expensive herb you can find. It is needed by raid guilds for all sorts of potions they need to beat MC, BWL, AQ40 and Naxx. Replacing it by a new one would make sense right?
No, they did break their rule. Some of the high end potions need dreamfoil still, like the Super Healing Potion. Why did they do this just to dreamfoil and not to the other materials I mentioned?
Ask the designers. I don't know, but somehow they want to create a two class community: the ones with BC and the ones without. The separation will be so intense that people might be forced to buy BC just because otherwise WoW wouldn't be a complete game.
From experience of other expansions of MMOG's (like the original Everquest) Blizzard doesn't need to worry about selling the expansion to their customer base: over 80% will buy it anyway, thats the number each MMOG showed when launching expansions. Hell, there is Guildwars, a game only based around making money with expansions as they don't even charge a monthly fee.
What does this mean for us? Throw out your valuable stuff, sell now. Empty your raid guild bank and sell that crap, it will be worthless 3 month after BC shipped. Who needs a +15 resist enchant (needing 2-3 nexus crystals) anyways if there is a better one someone from BC can do to your item?
Of course there might be another behaviour coming in: as the high end material becomes cheap more players can actually afford those enchants or weapons, armor whatever. We will see.
I personally don't like the separation they put into those new skills. In case you want to check your skill and what material it needs check http://www.thottbot.com, click beta and look up your trade skill on the left. Not all recipes has been found yet, but the glimpse you get will tell you what items will loose value, and which don't.
I wished Blizzard would have tied in everything we worked for so hard into BC in a much better way. Why not leaving Elementium (as an example) in there? For a level 70 guild its easy to beat BWL, so farming it there would be easy and fun. My bet is that BWL will be an empty haunted place soon. Bliz can turn off the BWL servers and no one would notice.
Now they simply cut the world in half. Forget what you needed in WoW, you need all new stuff and we will live in the new Outlands for a long time, as only there you will find what you need to enchant, tailor, cook or whatever you do while waiting for the PvP to tick in.