I don't personally PO from specifically sideshow, but no I'd not be happy about it obviously, but I wouln've be 'pissed to say the least' about it either. I'd enquire if my PO came through, enquire when it's being sent out. and if the item's already out, try to cancel the PO and buy it, which I've actually had stores offer me when I asked them.
But no, if I'd be guaranteed to getting my copy and a solid date attached, no I wouldn't be completely pissed off, I'm not an 11 year old that can't deal with some tough luck. Cause it ain't more than that. In fact, it's not even tough luck, it's probably the normal release date, the people hunting with those codes are probably just lucky. Well, they put a hell of a lot more effort into it, so I say fine, good for them.
Be a bit of a sport about it man, you're sounding like a spoiled kid. No it's not cool of them I agree, but that's about it. Just, not cool.