Why can rogues need shields ?

Q u o t e:
Only after a certain level (or possibly ilevel, not sure). At low level anyone can still need anything as far as I know.

If my memory serves me right, an item above iLevel 70 is subject to Need before Greed rules.

Q u o t e:
Is this going to get fixed in the near future ?

It's not really considered broken, the limitation was intended because some items of a lower level aren't always clear cut who they should go to, or benefit the most. A levelling balance druid, for example, could encounter some difficulties gearing up without having a shot at grabbing some cloth loot.

Q u o t e:
Ok, on the other hand, because of this system, balance druid can need on mail and he has no use for it whatsoever. I level mostly through dungeons and before I reached level 40-45 I never saw any resto shaman drops in dungs. Then first mail chest with int and mp5 dropped and druid needed on it, won it and instantly quit ... From that perspective this system completely fails.

Most unfortunate indeed, but this has always been a possibility. All it takes is someone with a great deal of greed and self serving tendencies to abuse that fact, and it'd be tough to come up with a system that protects everyone in all cases. As you can see from the most recent Need before Greed changes, we are trying to make it a more solid system and are certainly not ignoring the fact you guys seek better protection from the selfish and inconsiderate.

Q u o t e:
Also the reason some specs have difficulties with gearing up at early levels is because Blizz hasnt touched drops in 5 mans and quest rewards in 5 years and guess what, they are outdated.

Some are indeed a bit out of date, we agree and understand that, and that is why the restriction to Need before Greed only applies from a certain iLvl and above. Whilst it is not technically impossible to go back and update all old loot to match the current state of classes, it would be crazy to do it now with such massive changes for most (if not all) classes in Cataclysm, and we feel spending masses of time on developing the future is a better investment than re-developing the past.

Q u o t e:
It was always a possibility but not encouraged the way it is now. I don't think you can control social behaviour solely through game mechanics by putting in that kind of ninja safe guards.

We don't encourage it in any way. In the past it was possible for all classes to roll what ever they wanted on what ever they wanted. Now that is much more restricted. We have not gone to any length to make it more possible, quite the opposite in fact.

For a long time people called out for systems similar to the one in place at the moment. Ok, so it doesn't protect all players at all times with all items, but it sure is a step in the right direction, do you not think?

Q u o t e:
You are encouraging it by making people much more anonymous through the cross-realm instancing. And by removing the need for community.

The LFD tool has not only massively alleviated the hardships encountered when trying to form a group for instances of all level, is has also made it (generally) a quicker experience, too. You're still able to form a group in the regular way, though. We haven't removed the choice to PuG players from your own realm or guilds.

Q u o t e:
You made rolling much more restrictive, but before those changes ninjaing wasn't nearly as common as it is now.

Your experiences may show this, which is fair enough, but I can guarantee this is not the case across the board.

Q u o t e:
If you give us players a chance to act decent we will.

You still have that chance. If everyone thought like you, the World (of Warcraft) would be an even better place. :]