I am a big fan of crafting and tradeskills in general. So my various characters in World of Warcraft cover nearly every possible profession. Nevertheless I not only did barely any crafting in Cataclysm up to now, I even sold the materials I gathered instead of using them for crafting. The reason I did that was that I realized that some players are very much in a hurry to skill up their professions, so much that they are paying rather silly amounts of gold for simple materials. The most basic ore of Cataclysm which I collected to skill up my mining skill I was able to sell for up to 15 gold per ore, 300 gold per stack. Now the prices are slowly coming down, and I'm pretty confident that at some point I can take those 300 gold I got for one stack of ore and buy several stacks of the same ore with it in a few weeks time. The same thing holds true for cloth, herbs, and the "volatile" elements. Sell now, buy back at a fraction of the price later.
While I was pondering this, I was also reading various comments on WoW blogs about the level of difficulty of 5-man heroic dungeons and raiding. And I made the connection, and realized that for those dungeons basically the same thing is true as for crafting materials: If you try to do them right now, a week after release, it will be hard. But with time they will get a lot easier.
This is not because I believe Blizzard will nerf dungeons or anything, but just a natural consequence of the system as it is now. If, for example, you group with 4 random characters for a pickup group today, chances are that some of them will enter the dungeon you are going to for the very first time, and that their gear is barely over the new "minimum average iLevel" requirement of the dungeon. Group with 4 random characters via the Dungeon Finder in a month, and chances are that people know the encounters better, and are better equipped. Group with 4 random characters in 20 month and that same heroic will be a facerolling AoE fest, because everybody is in iLevel 500 epics and did all those heroics a hundred times.
At least as far as dungeons are concerned, this is good news. Do you love wiping and extra-hard dungeons? Do them now! Would you prefer to have an easier time? Just wait! Do you have several level 80 characters and are worried that those you don't play will fall behind? Don't worry, the ones you don't play now will be able to equip themselves much cheaper than today from the auction house, and through easier dungeons quickly catch up.
The only possible pitfall in this plan is raid dungeons. Yes, raid dungeons will become easier as well with time. But if Blizzard manages them like they did in WotLK, the raid dungeons of today will also become obsolete tomorrow. So if you wait too long before visiting a raid dungeon, you might find that place completely deserted, and nobody willing to go there any more. This is exactly why I'm hoping for a looking-for-raid functionality in a future patch.
The funny thing about the effect of time on Cataclysm dungeons is that many people don't realize it. Thus right now you'll here a lot of comments that Cataclysm dungeons are "hard", some even calling them "too hard". But I bet that if you read blogs in a year or two, you will see people complaining how the Cataclysm dungeons are "easy", or "too easy", with various comments on how Blizzard is catering to an audience of low intelligence. But if you look at it without prejudice, Blizzard probably made the Cataclysm dungeons as hard as they could get away with, and the thing they are catering to is not "low intelligence" but the natural desire of all players to see their characters get stronger over time. By having dungeons always at the same difficulty level for the two years between expansions, and by allowing players to become stronger with time, the result of dungeons becoming easier is inevitable. The good news is that one *some* point in time the dungeons are at the perfect difficulty level for any given individual. The bad news is that this point in time is different for everybody, and we'll be forever stuck in beating the dead horse of the discussion whether WoW dungeons are too hard or too easy.