Last time we checked in on renowned Steam demigod PalmDesert, he'd just pushed his Steam level to 600. At the time, he had the highest Steam level in the world. He still does, only now it's broken 1000. PalmDesert is a 35 year-old man living in Japan. He owns a whopping 5029 games, a significant chunk of Steam's entire library, which is comprised of 7481 games and DLCs. He recently became the first person to hit Steam level 1000, something only he has done so far (his closest rival is closing in with a Steam level of 993). Currently he's at level 1046. As is often the case, he crossed a new threshold before Valve even got around to designing a graphic for it.
PalmDesert has been at or near the top of the Steam level rankings pretty much since the system was implemented in 2013. The man does not eat or sleep, apparently. He does, however, play a shitton of Rocksmith.
A person's Steam level comes from owning games, participating in events and crafting Steam badges from trading cards that come from games. Higher Steam levels earn you things like friend slots and the ability to showcase things (items, favourite games, achievements and so on) on your profile. As you can imagine, PalmDesert's profile is decked the fuck out.
Yes, Valve has very effectively game-ified the act of spending money on their store. It might strike you as a bit icky, but it's hard not to respect PalmDesert's dedication to staying on top for three years. And counting.