How do you measure your greatest gaming experiences? In the intensity of your involvement with the game - be it emotional, physical, sensory, cerebral? I think that's as good a yardstick as any. But it can put a professional games reviewer like me at a disadvantage.
I think Super Mario Galaxy 2 is an astonishing achievement, but I played it during working hours in a bland office block. I admire StarCraft II immensely, but in all honestly it's not the sort of game I would play for my own leisure, and reviewing it was an intellectual exercise. Halo: Reach was a tremendous summation of a series I love, but I'd played and written and thought about these games so much over the years that, at the fifth time of asking, I found I had little left to say - or to feel. The well had run dry.
So it shouldn't be a surprise that, when I came to draw up my personal top 10 of the year, the games at its summit weren't necessarily the best, but were the ones I'd played away from work. One of them, the lovely Dragon Quest IX, managed to fill the many idle moments of a relaxing week in the sun without ever turning it into a busman's holiday.
Its soothing rhythms spiced with gentle reinvention held the attention, while its plain-spoken, heartfelt innocence cleansed the palate. Suddenly I wasn't a detached writer any more, I was a hungry kid again, wolfing down Level-5's wholesome comfort food.
When I came back from holiday, refreshed, Codemasters released F1 2010, its maiden FIA-approved Formula One title and a game in which, as a fan of the sport and of racing games, I had a natural interest. What a happy coincidence. But these reasons alone don't explain why I played it so avidly, or why I think it's one of the most exciting games released this year.
Just like Dragon Quest IX, in fact, F1 2010 is a subtle retooling of a game type you think you know, keeping the basics intact but changing the priorities. The moment-to-moment experience is the same - attack, heal, loot; brake, turn in, accelerate out - but it's been arranged into a beguiling new pattern and given a potent new point.
In another very conservative year for gaming, F1 was actually one of the freshest experiences to be had, and when you consider that it's both a sim racer and a licensed sports game - two of the most staid, iterative, change-resistant genres imaginable - that's quite an achievement.
Codemasters' big idea was to let players "live the life" of a Grand Prix driver off the track, taking part in contract negotiations, car development, team-mate rivalries and media interviews in order to shape an actual career over multiple seasons. This, we hoped, would serve up the politics, scandal and scuttlebutt that every F1 fan enjoys almost as much as the racing.
One reason we love to watch sport is because of the stories it tells - and no sport reflected that better in 2010 than F1's dramatic and competitive season. Yet spinning stories is something sports games (with the possible exception of the football management genre) are notoriously bad at, when they bother to engage with it at all, which is almost never.
As it turned out, Codemasters' attempt was over-ambitious and under-realised. The interviews were dull and had no discernible impact on the course of your career, car development was a series of simple unlocks awarded for completing lap challenges and the wooden presentation simply wasn't capable of human drama. Even the developers admitted they'd fallen short. Perhaps it was too much to hope that a game labouring under the demands of one of the world's most powerful and exacting licensors could ever be raw.
But the thing is, it could be, and it was. F1 2010 told utterly gripping stories where it matters - on the track. And it told them on multiple levels: over a lap, a race, a weekend, a season and a whole career.
Codemasters' Racing Studio has long been expert at conjuring track-day atmosphere and drama, both in the hyperventilating excess of GRID and DiRT and in their more reserved, but no less compelling predecessors, TOCA and Colin McRae. Great graphics, combative AI, fun formulae and direct handling are their well-established stock-in-trade.
The developer's new Birmingham team took all these elements, built on them with some fantastically evocative dynamic weather effects, and then married it all to a supremely well-judged interpretation of the F1 race weekend. It's a challenging motorsport that many developers have struggled to make palatable without losing its bite; Codemasters' genius was to give it room to breathe.
At first, the decision to include mandatory practice and qualifying sessions and force a minimum 20 per cent race distance in career mode seemed mad. It does inflate a run through a whole season to epic length. But it's also the smartest thing about the game.
The arc of a race weekend is emphatically conveyed. You progressively master your twitchy hypermachine on a new track, making mistakes, reining it in, learning the rhythm and then tentatively pushing at its limits, whittling down those lap times. Then comes the race where you have to balance your hard-learned consistency with quick responses to changing conditions, and gamble all those precious minutes of smoothness and concentration on one split-second moment of risk-taking.
The structure is both hugely involving, and necessary to the steep learning curve of F1's extreme cars and monumental roster of race tracks. The newer and less familiar designs of ubiquitous track architect Herman Tilke are an education in themselves. They can seem dry on TV, but from the cockpit they offer totally engrossing and surprisingly varied challenges, from the technical posers of season opener Bahrain, through Istanbul Park's thrilling, dust-blown expressway to the exotic sunset spectacle of Yas Marina.
And despite the failings of the game away from the asphalt, this parade of great race weekends - each one a thrilling hour-long gaming episode in its own right - does form a compelling career trajectory. The focus on competition with your team-mate is cute, but the game is shaped by the decision to start you in a lesser team. You can then choose to help develop it or attempt to earn enough reputation (a sort of performance-based XP) to win a better seat.
Starting in a Lotus, fighting tooth-and-nail in the pack in an effort to get your hands on a Renault, and then doing it all again with Ferrari as your goal is a more meaningful and powerful motivator than simply slugging it out with Hamilton for a world championship. It's a journey, it's an adventure, and the grand sweep of it makes every moment of the game more involving.
Racing games are universally terrible at context. Even the best of them structure their fun in ways that are arbitrary, abstract or forced. It's been a great year for the genre, but even the rip-roaring thrills of Blur, Hot Pursuit and Split/Second left little in the way of aftertaste, while the extraordinary Gran Turismo 5 could be mined for moments of unforgettable intensity - but you needed commitment and patience to find them.
F1 2010, on the other hand, draws more from its context than a lot of action and adventure games manage to do. Through a great understanding of both the sport and the timeless, slow-burning love-triangle of driver, car and track, the whole becomes a great deal more than the sum of its parts. It takes you somewhere you've never been before, no matter how often it's been tried: into the body and mind of a Grand Prix racing driver.
That's why my involvement with it was more consistently intense than any other game I played this year. And why, despite the deep familiarity of the sim racing routine, it was something so few other games managed to be: it was new.