Today in my morning paper break I came across this post complaining about the state of GTK+ development. I knew GNOME was going its own way but I didn't realise GTK+ was coming along for the ride too, although given it's history it shouldn't surprise me. Even from before GNOME 2, Gtk+ was engulfing non-toolkit functionality for the purposes of control and now they've simply merged into one.
To be honest, ... i'm a bit surprised anyone is still writing desktop applications in C anyway. I guess when the primary alternative is C++ ... there's a pretty compelling reason. Unfortunately Java just doesn't seem to have caught on much in the free software world (or 'open sauce'). Historically the reasons are obvious, but a free, stable, and performant version of openjdk has been available for some time now, and both the platform and the tools are better than they've ever been. And in my experience the current JRE runs better on even an 'unsupported' GNU/Linux distribution than it does on Microsoft.
Instead developers seem to be focusing on scripted-glue technologies like Python, which aren't powerful enough to do significant processing without calling a library, and have other limitations like poor thread support - I think I just heard the mid 80's calling, they wondered what you did with the last few decades ...
And where needs require it for the re-use of existing libraries, I've found interfacing with C to be quite straightforward and sane from Java - more sane than just writing the GUI in C.
Here's one interesting data-point, the post above is complaining about maintaining software against a moving target controlled by a corporate interest with other goals in mind. However, I can take 13 year old Java like Dusk, and run it on the current platform - unchanged. Not only are the api's incredibly stable and long-lived, they don't need to be discarded to move forward (and the planned modularisation mechanism will prevent the platform growing forever). Try doing that with a 13 year old gtk+ app - apart from the dependency hunt you're left with unpatched and insecure libraries if you can find them all. Not that Qt would be any better - C++ is a big pain of dependencies which go right down to the compiler and the standard library which makes it even worse, you might have to build your own compiler first. I don't know about Apple, but Microsoft stuff is arguably worse with forced upgrades tied to each version of the ide usually based on flavour-of-the-month experimental api's which silently 'disappear' after a couple of years.
Pretty ironic when Oracle of all companies is producing a more developer friendly platform than a so-called "open sauce" company (or Ubunutu). Actually it's not ironic at all, they're only working on the platform and not (apparently?) competing with their own customers. I guess one problem Sun had is that they always wanted to be the next Microsoft, but Oracle just wants to make money; and although there is correlation they are not the same goal. All these new 'platform' providers seem to be falling into the same trap (except it isn't Microsoft where anyone wants to `go today').
So when JavaFX finally becomes fully free it might be a good opportunity for free software (and "open sauce") developers to investigate a modern, GPU-accelerable, cross-platform toolkit. It still has a way to go, but it's getting there.
Although I don't expect anything to change much as it's unlikely Java will ever be fashionable again, due in part to misinformation but also simply because competitors and developers have a financial interest in it staying unfashionable. I'm sure the Apple and Google mobile platform juggernauts will be consuming increasing developer resources as well with their casinos masquerading as shop-fronts (remember, the house always wins!).