Speaking from a UK perspective, there are some subtle differences in niche terms used I find. For example, I pick up more UK users on the phrase “gambling” than “casino”. Largely the UK public are well behind and don’t have the “Vegas” mentality. We grew up with “fruit machines” and “pontoon” rather than “slots” and “blackjack”.
That said, times are a changing. There is a very handy tool here that helps you differentiate between UK and US searches:
http://tools.seobook.com/general/keyword/suggestions/
It’s an advanced OVT basically.