It's inspired by the GT4 race car that currently competes in the British GT Championship, and features a host of upgrades that are designed to win over track-day enthusiasts.
The most important of these is a 2.0-litre petrol engine, which has been tweaked to produce 205bhp compared with the regular car's 158bhp.
The suspension has been uprated and is adjustable so it can be optimised for different track conditions, while aerodynamic tweaks help the car slip through the air with more efficiency.
As yet, Mazda has not confirmed whether or not the GT will go into production. Indeed, the finer points of the car's set-up are still being worked on even the engine output hasn't yet been finalised.
What we do know is that if the car does go on sale, it's likely to be a Roadster Coupe (folding hard-top) and will cost around 30,000.
What's the 2012 Mazda MX-5 GT Concept like to drive?
In its current state of tune the GT's engine has the same characteristics as the regular MX-5's, in that it needs plenty of revs to do its best work.
Still, the hike in power means the GT is considerably faster than the regular car, and it revs to a heady 7800rpm before you have to change up using the slick six-speed manual gearbox.
Mazda MX-5 GT Concept not yet confirmed for production
Mazda won't divulge any performance figures yet, but be assured the GT is very brisk indeed.
It's also very loud, with the exhaust bellowing and booming to a raucous crescendo as the revs rise. Mazda says this will be toned down if the car goes into production, and although it sounds great at present, that's probably a wise move.
The car we drove also had a very sticky throttle pedal, which was hard to modulate properly. However, the fact that our car was a pre-production mule was to blame for this foible.
From a handling point of view, the GT doesn't feel that far removed from the standard car, which is surprising given the comprehensive changes Mazda has made.
The ride height has been lowered by 35mm, the springs are completely new and the shock absorbers have been heavily modified. This means the car feels a shade tighter when changing direction, with better body control in corners.
It all combines with the classic MX-5 characteristics light weight, neutral balance, rear-wheel drive and sharp steering to make the GT great fun to drive.
The suspension modifications mean the ride is firmer than the standard car's; you feel most imperfections in the road surface and are jolted more over potholes. However, the GT won't make you wince.
What's the 2012 Mazda MX-5 GT Concept like inside?
Aside from a few racy-looking bits of trim (carbonfibre panels on the dashboard and Alcantara gaiters for the gearstick and handbrake), the GT's interior is much like any other MX-5's.
That means the dash layout is clear, if a little heavy on buttons, and the visibility is pretty good front and rear.
The cabin feels impressively solid, too, and although many of the materials are hard, the MX-5's cabin still manages to look reasonably classy.
The low-slung driving position feels suitably sporty, and the Recaro seats hold you in place snugly. True, the steering wheel has no reach adjustment, but it's still pretty easy to get comfortable.
Both of the seats are surrounded by plenty of space and there's even a half-decent 150-litre boot. As a bonus, you don't lose any of that space when you drop the roof.
Should I buy one?
Affordability has always been central to the MX-5's appeal, but the GT version looks quite expensive at a predicted 30,000.
The regular 2.0-litre Roadster Coupe model costs around 7000 less than that, while the rival Mini Roadster John Cooper Works is also considerably cheaper at 24,860. In fact, 30k is about what you'll pay for our favourite versions of the Audi TT Roadster and BMW Z4.
Granted, the MX-5 GT's extra track-day ability will make it worth the premium for a dedicated few, and for those people it will provide immense amounts of fun. However, we can't help wondering if the GT feels a little too similar to the standard car to warrant the hefty premium.
As for those who have no interest in regularly pounding around a race track and just want an enjoyable road car, the standard MX-5 is more than sufficient.