You might also want to check out OpenGEX:

http://opengex.org/

You might also want to check out OpenGEX:

http://opengex.org/

I read a bit about that, but it doesn't really seem to have a lot of support (there's a few unofficial exporters I suppose). I also read a lot of criticism on the way it stores stuff. (For example animations are part of a mesh)

The exporters on the opengex.org website are official. As for the criticism, please realize that not everyone who posts an opinion on the internet has the same qualifications. Some people are educated and experienced, and they probably know what they're talking about. Other people have never actually been a professional software developer, and yet they like to bash everything as if they were some kind of expert. There is a lot of praise for OpenGEX out there in addition to the few negative opinions you might have read. It's up to you to decide whether somebody's opinion actually holds water based on their qualifications. And if you can't find out what their qualifications are, then they probably don't have any.

I read a bit about that, but it doesn't really seem to have a lot of support (there's a few unofficial exporters I suppose). I also read a lot of criticism on the way it stores stuff. (For example animations are part of a mesh)

You should consider, that most intermediate formats are really only a temporary step between your modelling tool and your game. FBX and collada are really bloated and are not suited for any serious game project. A common way is, to export to one of the intermediate formats and then convert these formats to a custom format which will be used by your game.

I've used collada for several years, but the (blender) support was really bad and the format is quite complex. Afterwards I have written a custom FBX reader I use up to now. The FBX format is structured in a more clearly way, but it is not a open format.

I would have wished, that I know about OpenGEX before I wrote my FBX converter. Collada and FBX are not designed to be used in a game engine and have lot of stuff which is not really useful in game development, OpenGEX has been designed to be used by games and I would try it out first nowadays.