I suppose I can see how the normal way of giving out treasure (randomly?) could be problematic for a DM, it certainly makes it harder for the player to get that holy avenger or whatever they've been dreaming of. But with my playstyle, I don't really mind and it's even kind of cool to be surprised with whatever treasure happens to be there when you pop that chest.
First, I'm just not the kind of guy that likes to roll on tables to determine things. I dislike random classes like wildmages, and random effects like the Rod of Wonder. I am aware of the contradiction that we play a game with dice, thus everything is to chance, but I see the dice as a formality and necessary evil.
Second, it's not just "What item they've been dreaming about".
If you drop a magic bow into the treasure, and no one in the party uses a bow, I think only the rare player will go "I shall now start using bows even though it has nothing to do with my character concept up until this point". This is especially true since 3e, where characters would have dedicated feats to certain weapons (or have weapon restrictions in their class), and if it doesn't fit their character, they just won't use it (in 4e, only certain classes benefit from ranged weapons in the first place, etc).
More than likely, it's going to go into the "sell in town" pile. And since I don't like selling magical items... It also hurts my idea of fantasy when the PCs have a golf bag of magical weapons they carry around, for the occasion they might need that Frost weapon, or a bow.
But I've mentioned elsewhere that my idea of magical items has nothing to do with +X, and that every character should get 1-3 magical items with a thematic suite of powers, and that's it.
I'm guessing your players don't have any problems with it though do they Rechan?
I only did the Wish list with one group, because they were serious players. They knew the rules inside and out, and we were playing serious. It was just easier, for me, to do the wish list then worry over the treasure I was handing out.
My second group are casual gamers who just want to roll dice, kill things, be awesome, and barely pay attention to their class powers. I don't track XP with them - I just tell them when to level up. They don't really care about equipment, and I don't really worry about handing it out - I just give them +x item and that's the end of that.
I am having to leave both groups due to moving, so who knows about the next one.
