Many people told me about good sides of the different OSes, but I'm don't find something new and ready-for-use innovation features in the OSes.
All unixes family has an old philosophy that doesn't support and can't support a good cluster technology. There are a problem of the architecture limits. Developers said -"Hey, we must to do threads it's a good and fast", but nobody from theirs all don't think that threads cannot migrate between nodes in example. Theirs don't thinks about flexibility in generally.
Yes, now I talking about kernels, take a look for the linux kernel, it's a huge trash of the infinite features. They includes a buggy source code for features, *bsd otherwise, they don't include something new, but trying to make a sense of the security and stable features. But we don't have an innovations both in linux or *bsd.
The main reason is the really old architecture.
I'm don't speak about closed OSes such as Solaris or non-unix OS m$ windows - it's a deadly OSes without future.
So, I think that in the time we will see new concept of the kernels and OSes generally, but who ia ready fir this?