The Burning Crusade did quite a bit to make tradeskills useful. While some were more powerful than others, almost all of them got something pretty nice, even the gathering skills. Tailors and Blacksmiths got a bit of an edge in gearing up for higher content, Leatherworking drums are one of the single most desired crafted items around for raids, Engineers got fantastic goggles and a pretty cool mount, Herbalists can pick powerful consumables, et cetera, et cetera. This is a major step up from life in vanilla WoW, where any tradeskills except Herbalism, Alchemy and Enchanting were almost entirely worthless.
Still, though, it kind of feels like crafting in WoW is... empty. The tradeskills are useful now, but I'm a strange fellow. The tradeskills need heart. They need flavor. I like my tradeskills having a larger effect on how you play. Leatherworking is actually a good example of this, from a conceptual point of view. I love the idea of drums having an active effect on things. It isn't just a passive stat increase that you equip or cram in your mouth. It's something you need to be conscious of, something you need to actively use. I don't really know how you could do this for all tradeskills, but I'd love to see more of it. No, those crappy nets don't count.
Another thing I'd like to see expanded from The Burning Crusade is location-specific crafting. Making my Spellcloth, Primal Mooncloth and Shadowcloth every few days seemed like an adventure, if a tedious one. Spellcloth was especially fun! You had to arm and prepare yourself before you hit the 'create' button until your gear was good. Fishing before The Burning Crusade was not nearly as useful as it is now, but I liked time of day and season having an effect on things. Stocking up on Grilled Squid in the appropriate season and using it to negotiate deals with rogues and hunters was great fun, I think. I'd like to see that come back in some form in Wrath, though maybe not as extreme.
What would you like to see out of crafting in Wrath? Are you hoping for something more dynamic, or are you a (wo)man of simple pleasures and all you need is a great big sword to be happy?