Whether to need or greed on frozen orbs at the end of a cross-server instance run was a question that already came up in my very first post about the new system, and one that was also commented on in other places. I believe that WoW.com had an article about it too, but I can't be arsed to find it right now since their search engine sucks. Overall I got the impression that people explained different rolls away as the result of different server rules and that many were of the opinion that eventually, everybody would just settle on needing.
Over a week later, this is so not what's been happening in my battlegroup (Cyclone EU).
First off, I really can't fight the feeling that the argument about different server rules simply doesn't apply, or at least not on Cyclone. I've mostly been running with people from the same couple of servers, and there's been no rhyme or reason to their rolls. Sometimes I'd have multiple people from the same server in my party and they'd all roll differently. So how do you explain that?
I sort of already mentioned this in my previous post, but my theory is that it used to be "all greed" on all servers, but that some people started rolling need under the new system out of a mixture of fear and greed. You can't trust those strangers from the other servers, they'll surely try to ninja the orb so you better roll need to get ahead of them! Except that if they all end up rolling greed as usual, you are the one who'll end up looking like a ninja. Oops.
If this is indeed people's way of thinking, for everyone to switch to need-rolling, everyone would have to be sufficiently scared and greedy. This doesn't seem to be the case however; most people still roll greed simply out of habit and because they don't seem to be that bothered about what others do. I've had runs where a single person blatantly ninjaed the orb and still nobody even batted an eyelash. With the current frequency of pug runs the damn things are practically raining from the sky anyway, so who cares?
I have to admit that I'm still a greeder myself, and in a fair number of runs it works too - the ever growing pile of orbs in my bank is a testament to that. Just before rolling I tend to throw a quick look at what others have rolled and if I see nothing but needs I'll roll need too... but this is rare. I'm not very thorough either; sometimes I look at the rolls, see a greed, hit greed as well, and then it turns out that the other three people needed. Still, I just shrug at situations like that and continue to roll greed because I really don't care that much about winning, and needing on a fairly common BoE crafting item simply doesn't feel right.
I just find the whole thing damn fascinating.