That is really difficult to notice unless someone has no work to do with his/her phone but only find and trying hard to find that tint, which is very lol-able stuff.I haven't really noticed that yellowish tint on gray backgrounds yet!
Anyway, it's recorded a record sale already without hitting US, and I am one of those damn proud owner of GS II,
Galaxy S II breaks Samsung's records, sells 3 million in 55 days - GSMArena.com news
Also I've updated mine to latest XWKF3 with baseband KE4 which popped up in Kies two days back. Battery back up is gotten better, Swype also got an upgrade, other things I don't notice yet, when I do I'll post back here.