Now this is also good game library. Someone leaves, someone comes up - development continues.
I used to think so too, but when you are part of something for 12 years and see how drastically the community and devs change, your eyes start to open up that there are libraries and communities out there that are better and treat their beginners better.
You're right, there is communication and assistance are important, but if I pay attention to how others treat me, I would not been able to create something working. I think in the first place should still be a tool that is suitable for a particular developer - the 99% completion depends on of the author, even if there is support from the community.
I suggest SFML2: you have not only graphics and OS managing out of the box, but also an audio and networking system, all in a nice OOP vest. Documentation is very good also, and community large enough to let google answers your questions.
Small bit of trivia... the guy that created the Allegro, Shawn Hargreaves, went on to work on XNA at Microsoft. It was also one of the very first graphics libraries ( along with Fastgraph and WordUp ) I worked with. Before that most people rolled everything on their own, including the rasterizer. Thank god for Michael Abrash...
Anyways, as someone who has been around a long time and worked with A LOT of libraries, personally... I'd recommend you reconsider LibGDX, and I'm not even a big Java fan.
