Maybe you’re here because you’re already a fan, maybe you are doing some research wether FbL is right for you. Below are my, totally biased impressions and summary of Key features and why you should play it.
I may edit this initial post depending on the comments below in order to deliver a community-driven overview of this game.

1. The rules. They are both easy to understand and apply ingame and flexible enough to allow for a fine granularity. In a group of GMs we discussed if there was a “best weapon”. We could not agree because each has its usecases - not bad for a system with 2 weapon stats and some tags on them.
2. The lore. It’s a fantasy classic with a surpising twist to it here and there. Without spoilering too much, halflings are all jolly and merry and friendly but behind closed curtains they hate each other, are alcoholics and beat their children. As a GM, you receive a treasure trove of background, legends, events, but from the perspective of the uncertain narrator, so there’s a wealth of room for your interpretation. Not two worlds will be the same and if you are playing on two different tables, you will most likely still be surprised quite often.
3. The campaigns By the time of writing there are three official campaigns available. Broadly speaking, they take well established elements of the lore (the “Bloodmist” that isolated villages for 3 centuries) and lets the players discover their reasons. And of course, save the world and/or carve out a good piece of it for the players themselves)
4. The flexibility & preparation required: Of course, if you’re not so much interested in the campaigns, you can play Forbidden Lands as a pure hexcrawl / dungeoncrawl. With little preparation required by the GM. The mechanics for travelling and resource management are excellent, the random encounters and tables to generate adventure sites provide you with enough tools to keep you and your players entertained for month.

Combat is much quicker resolved (and, as stated above, much more streamlined and fluid than pathfinder or DnD). A character has at most 6 Hitpoints (his strength), and losing those points makes him weaker (because they use strength to do melee attacks as well). At the same time, becoming “broken” takes you out of the fight and you receive a critical injury, possibly, but not necessarly, death. Call it - more dangerous, but less deadly.

What do you think? Why do you love it? What’s missing in your opinion?