In addition to replaying Deus Ex, I've been working my way through Grand Theft Auto IV. I think it's the best of the series, and I think that's because Liberty City is perfect.
The previous games had this too, from what I've read. I've played them all, but I wasn't in Miami in the 80s or Los Angeles in the early 90s. They feel like a caricature of those places—which they are, of course. Liberty City is as well, but it's also the best re-creation of New York City in any game I've played.
By best I don't mean most accurate. Liberty City isn't a perfect copy of New York by any means. The layout is generally the same, but the city's too small, one entire borough is missing, and the geography is similar but not accurate. But I think GTA4 proves that kind of exact copying is unnecessary.
The first thing I noticed when I was wandering around Broker (GTA4's Brooklyn) was that I immediately recognized it. The geography is wrong, the streets are wrong, the names are wrong, but they re-created every neighborhood's feel. The culture, the kinds of buildings you see, the languages you hear, the food, the architecture. Hove Beach is Brighton Beach the second you walk out and see the lines of shops and Cyrillic signs. Outlook is Prospect Park once you see the park itself, the slopes of the streets, the old rowhouses. Lancaster feels uptight just like the Upper East Side. South Bohan is the concrete block that so embodies the Bronx, complete with memorial murals spray-painted on the walls.
When you play GTA4, you are stepping into New York. It's a fictionalized version, still a caricature, with every aspect of the real New York stretched to the extreme. It's the crime-ridden, broken down, seedy version of New York that ended fifteen years ago but still persists in fiction because, while you might not want to live there, the tough as nails New York that challenges and threatens you on every corner makes for better drama than the safer than Provo, Utah New York of today. Yet it still feels just right.
This makes the game. As far as gameplay goes, GTA4 isn't much different than the previous entries. The driving system has been modified, for the better in my opinion; the previous games fucked this up royally. You would think a game based on thieving autos would bother to have a decent driving mechanic from the beginning. There are still plenty of dumb design decisions. Which brings me to an aside—there is no excuse to release a game on the PC that does not have the ability to save anywhere, at any time, in as many slots as I want. If you think that ruins the experience, you're dumb and you're welcome to not take advantage of it, but for the love of all that is holy, STOP LIMITING SAVES. We finally got rid of jumping puzzles, this is the next relic of the 80s that needs to die a horrible, horrible death. Especially when your missions are as unforgiving as the ones in GTA. Stop. It.
Anyway. As I was saying, GTA4 isn't a massive departure from the previous games. It's so much better than them because of Liberty City. The city has personality and is a character in its own right, just like the real New York. Setting is one of those things that can take a game from good to classic. As an example, Total Annihilation and Starcraft came out around the same time, reached a similar audience, and both were exceptional games. Total Annihilation was as good or better than Starcraft, had (and still has) a strong cult following, but never gained the kind of success Starcraft did. One big distinction between them was that Starcraft had a strong setting and a storyline that captivated its audience, while the setting and story of Total Annihilation was incidental at best. Few people can remember anything of it beyond the names of the factions. It had to survive purely on gameplay strength, and while it had that in spades, it just wasn't enough to grab players the way Starcraft did.
GTA4 is one of those games that combines strong gameplay with a truly memorable setting, and I don't think it will be forgotten.