Car racing games have always fitted into two camps - simulation, or arcade. The Xbox 360-exclusive Forza series has always fitted squarely into the former, with recent versions bordering on total anorak levels of simulation, down to recreating the flex of a tyre's sidewall. Car geeks like me love this, but it does make straight-out track racing games a bit inaccessible for those with less pointy heads.
Forza Horizon seeks and succeeds in addressing this lack of balance, at the expense of some simulation tricks, but without diluting the spirit of the original series. The tracks are gone, replaced by hundreds of kilometres of Colorado roads, which all lead to the Horizon Festival, a huge music event with racing tied into it. There are plenty of car-related tasks to perform, from winning set races, street races - even cool sponsor challenges like racing against an old Mustang fighter plane in a grumpy Mach 1.
There are missions to find old cars hidden in barns in the middle of nowhere, and speed cameras to blast past at maximum velocity. Races and challenges earn points, but the real currency in this dumbed-down Forza spin-off is fame, and you earn your celebrity by winning and driving like a dick. Caning around the Colorado roads, nearly all of which contain traffic, you get extra points for driving at high speeds, more for close calls with other vehicles or pulling off massive drifts or big air. Where Forza 4 rewarded for consistent lap times, no-crash races and well-sorted car set-ups, Horizon goes for flashier form, but the handling is still sharp enough that it's a rewarding experience.
That said, you wouldn't be able to drag the back wheels of a 700-horsepower supercar on the grass verge at 250km/h and get away with it in Forza, but it's stock in trade for Horizon.
Graphically it's a beauty - cars are well-rendered, endless roads are the same, day gives way to night in stunning fashion and the odd cut scene that pops up is fluid and good looking. The soundtrack, if you prefer music to the aural experience of manking great turbo V8s at their redline, has big name acts from a few different genres selectable GTA-style by cycling through radio stations. There will be, as with all of the Forza series, a huge amount of downloadable content on an ongoing basis, with regular car pack releases.