Kerbal Space Program has been massively popular over the years because it's a smart/funny game, of course, but it's also remained on people's radars thanks to the tireless development and update work of the team behind it. Work that, for the original developers at least, is now coming to a close. After years of betas and tests and tweaks and additions to the game's core premise — shoot some little dudes into space — the original developers have written a little note, thanking fans for their support and expressing their desire to move onto other things.
All good things must come to an end, and so it is for us. It is time for each of us to move on from Squad. Kerbal Space Program is an incredible game and has truly been a joy to create. We have greatly enjoyed working together with such a tightly-knit, professional, and talented development team, and with such a wonderful community. Over the last update cycle we've taken KSP to new heights and achieved great things with such a small team. We've finished work on update 1.2 and when Squad releases it, it will be a product of which we can be truly proud. We hope you share that opinion and we hope you enjoy playing it as much as we loved creating it.
Thank you all for the incredible community support. So long, and thanks for all the snacks!
Signed, in no particular order, your Kerbal developers Mike (Mu), Bill (Taniwha), Nathanael (NathanKell), Sébastien (Sarbian), Jim (Romfarer), Brian (Arsonide), Chris (Porkjet), Nathan (Claw)
For an idea of how long these guys had been working on the game, it was first playable for the public in 2011 (which is when I first wrote about it), and became popular as much for its spacecraft creation suite as its excellent physics. Even Elon Musk, a guy actually trying to shoot people into space, is a fan.
Of course just because the original development team is stepping away from the game doesn't mean it's dead. While most of the original developers are moving on, a different post on the game's forum says that new talent is being brought on to replace them, with the goal of continuing work:
There's an important amount of new content, besides this new update, that we're currently working on. This includes more free updates, full expansion packs with an incredible amount of new content and much more!
We're also experimenting with new technologies and platforms to expand the KSP experience towards new horizons.