He said "I'd be happy to hel..... oh, wait. This phone says Orange on it. Get tha hell outta my shop!"
You'd be much better off taking it to the Genius Bar at an Apple Store because they're more likely to just swap it over for you there and then, and more likely to have dealt with this issue before (so less questions!)
There are a few threads about these yellow displays already.
Apparently a lot of the new iPhones have this warmer tinted display now. Personally I don't consider it to be a defect, it's just that no two displays are 100% identical, like when you buy two tins of the same coloured paint but with different batch numbers.
I spoke to an 02 employee today in my local retail outlet about the warmer yellow screen on the iphone 4.
'Oh we've not heard about that before', they said.
I showed them the comparison between their display model, and mine.
'Oh yes their is a difference', they said !
The employee even pulled out their own phone, and hers was with yellow tint too.
Asked how long i'd had my phone, which I replied was just under a month.
'Oh, we've have to send it off for repair'.
To be honest I prefer the warmer yellow as ive found after playing with the shop displays, I dont need to raise the brightness of my screen as much as the baby blue one, thus possily saving on a bit of juice.
I just wanted to test the reaction of the store staff and what they would offer as a resolution.
I ended the conversation by saying......
Apparantly an apple genuis bar will swap it straight away, I said, and the reply was 'oh, yes they will and remember to take the box'
I kinda got the feelin they were guarding the stores stock with a three headed rottweiler guardian !! lol.