As a Kiwi, I probably fall more towards the UK gaming sensibilities.... but I've spent 4-5 years living in the US and Canada, so I've had some feel for the environment there as well. My personal observations (which may be wildly inaccurate)...
- UK game settings tend to be "grittier" (low magic, high bloodshed) than US game settings. Some examples:
- Warhammer: heavy Lovecraftian themes, chaos triumphant, and points-of-light almost overrun by vast evil
- Warhammer 40k: everything is war, and even the "good guys" are uber-fascist religious nutjobs.
- Dragon Warriors: grim medieval setting with corrupt lords, downtrodden peasants, and soul-less fey.
- Judge Dredd: similar to 40k, but with even more police-state overtones.
- Slaine: the primary "heroes" are blood-crazed berserkers who scorn civilized culture and leave mounds of skulls.
- There seem to be higher expectations for PC casualties in UK games, even when playing supposedly low-casualty games like 4e D&D. In my gaming experiences in the US, the groups I've played with tended to see PC death as a bit of a shock/tragedy, whereas the local groups here almost expect PCs to die every other session. Some of them even relish it.
- There is far more emphasis on "gaming with close friends in long-established groups, in one of your houses in the suburbs" in the UK/NZ. Probably because we have so few public RPG venues (stores, conventions, etc) compared to the US. This changes the dynamic of play somewhat. It's more beer-and-chips, a lot of in-jokes, go out to lunch or dinner together, know each other's family and jobs well, etc. It also can mean a slightly more eclectic mix of people. It's not always easy to find new members of the group (much smaller population, fewer venues), so you tend to put up with player "eccentricities" a lot more.
Again, my observations only... which means it could simply be based on the groups I've played with, and the settings I've played in. Personally, I reckon gamers are gamers. Apart from the [terrible] beer, inability to understand rugby, and mis-spelling a bunch of words that should have a "U" in them (like armour and honour), my American gaming brothers seem much like gamers anywhere else.