This phenomenon isn't limited to the decade marker - every year there are similar lists - but the ten year milestone carries with it a sort of significance. It represents the passage of time and the changes during that period, and it's a good signal for everyone to take a breather and look at the state of things, for several reasons.
Think about it: as human beings, we can hope for 10 (dare I hope for 11?) cycles of 10 years in the whole of our lives. That makes the 10-year mark inevitably linked to our own life milestones. It's a nice, even number too: if you were born in 1973, certainly '83, '93 and '03 were all significant for you - decades of your life, your teens turning into your twenties turning into your thirties. Then there's the extra significance of the decades themselves turning over: 1990 to 2000 to 2010, easy units that describe our cultural experiences in fashion, music, family, and careers.
It's easy to dismiss these lists, though, just because there's so many of them, and so little consensus. Certainly everyone has some opinion on a plethora of things, which can make for both fun or boring reading. However, this doesn't make lists less important to us. According to Umberto Eco, an author and intellectual curating an exhibition called "The Infinity of Lists" in the Louvre, we make lists to help us understand and scope the concept of infinity (check out the article, it's extremely interesting).
In fact, this is an ideal time to record your breadth of experience, things you know, and things you love. Imagine that every 10 years you composed a list of the top hobbies you picked up, or the top tweets you wrote. Even better, the top craziest dreams you had, or the top plane rides - anything!
You only get 10 (11?) chances to generate these interesting cross-sections of your life. What insight can you gain from younger versions of yourself, each of which were so enthusiastic about things you have now passed by? What will you find that can inform your designs for the future?
As Umberto Eco says in the article linked above: "If you interact with things in your life, everything is constantly changing. And if nothing changes, you’re an idiot." A bit harsh maybe, but good food for thought.