I want to share with you the method in which I add Magic Items to the adventure.
Currently I use the DMG method of what level items to add to the treasure parcels. Then I look through the Character Builder to find magic items I think the party needs or would like. I try to find items that will work for the party, i.e. you shouldn't find any magic items that simply doesn't work for any character. I plug these magic items into the proper level slots and print out the cards to present to the party. As it stands, the party will always get items they can use, but you may not get items you would want or would work as upgrades to your current items.
The reason I am bringing up this topic is because I was rolling a new (but already established in other games) idea for presenting Magic Items. In the new way, I would simply put Level 19 magic item in the Treasure area of the adventure or encounter. When you pass the encounter and search I tell you what you find and add "and you find a Level 19 magic item." You would identify the item as normal according to the level of the item. You would have to find a new way to distribute the items throughout the party. When the character gets the "Level 19 magic item" he/she can go through the books (or the CB) and find a Level 19 magic item he/she wants or needs and that's the item he/she gets.
It would still be like I put in all items the party could use, but the players would have more direct control of what his character receives. Obviously the biggest problem this might bring up is the cohesion or verisimilitude of the game. Would it break down the fantasy world we create in our minds too much to be worth it? Is it too much to give the party exactly what they want? Or will it simply things and be helpful to the party?
Now here is where you guys come in. What do you guys think? What are the pros? What are the cons? What do you like about the idea? What don't you like about the idea?