Shenmue is special to me for all the reasons everyone has said. For me, it's the incredible music, moving story, interesting characters, and the magic realism (my favorite genre). Something I think not a lot of people mention or appreciate about Shenmue is that it was pretty much the first game (and I can't think of another since) that atmospherically created an ordinary, even mundane world, that felt realistic. And yet, there are little hints of magic that start to develop and a great ancient secret or mystery buried in that, that slowly emerges as the series progresses. So you've got this great and unique mid-80s setting, so it feels modern, like home for many of us, but there's no internet, nothing to make the world seem small and less mysterious. On top of that, there were pretty much no games with changing seasons when Shenmue was released. That was wicked special at the time. So, it perfectly captures that wonderful feeling better than any game I have ever played. Also, it's Sega, so it just makes Christmas better.
I will never forget the 9/9/99 EGM magazine with the very first Shenmue preview. I still have it, and I'm still wildly impressed by the graphics, the style, the whole vision as described and shown in the screenshots. There is really nothing else like it. Almost every game then and today is overtly fantasy, or military games, or some combination.
Plus, the Dojo. Shenmue has a ridiculously close community, all of whom have similar taste in games, music, movies, etc., so that's definitely a huge part of what keeps it fresh because we've all been friends for so long, some since the beginning. Shenmue was always community oriented. Certainly, had Shenmue and the DC been a financial success, the series would have gone in the direction of community interaction as the successor to the original Passport, another interesting bonus that made the first game very special. Every part of it felt like you were discovering something profound by entering into a true virtual world.
I don't know, I think everything about Shenmue was just like destiny. It came at the right time in our lives and in Sega's history. A big part of it is that it was the crowning achievement of the Dreamcast, and that system was so much fun, and it was just such a great time for gaming all around. I mean, it wasn't too long after the first 3d cards, everyone was excited about the nextgen consoles and the amazing new graphics we were going to get, speculating on where it would lead, and so on. It was a very interesting time, and Shenmue represented this huge new vision that everyone wanted to be a part of, and if you were one of the few people with a DC, it was like you had been given a key to another world. That's what it was. It was like we discovered a world together.
If I could go back and live those years over again, I would.