...a decade ago. Since then it hasn't really had any significant commercial viability IMHO so it long since became a hobbyist OS and if anything, this is more or less proved by the very small scale operations of the likes of Castle and ROL. As such, it can potentially actually move along in directions which a commercial company might not have taken because of commercial pressures.
Whether there are enough people left in the community with the skills, time and willpower to make any of those changes remains to be seen, though we've certainly seen a big surge in interest at ROOL since we started making real ROMs. But even a "big surge" doesn't get you all that far since it's all relative to the level of active developer interest beforehand, which was broadly speaking "almost nothing" (unsurprisingly).
There are still one or two killer applications around - ArtWorks being an obvious example - but finding anything unique is difficult these days, unsurprisingly, while finding missing stuff is easy. I do worry that a lot of the directions people want to take the OS are being considered because they want to make porting easy, but if all you want to do is port applications from Linux, you may as well just go and use Linux instead! You'll have cheap, powerful hardware available and a wide range of distro choices. Some of ROL's developments seem more aimed at making life a bit easier for the applications programmer and that seems to me to be a more astute direction to take.
I always found that using Windows was just awful in comparison to RISC OS and - now, I know I'm going to ruffle feathers here but I'll say it anyway - Linux GUI environments just seem to be a bit of a bad joke. Bad experiences with Mac OS System 7 through 9 along with its very poor and buggy initial implementation as OS X had meant I dismissed and ignored Macs for many years, but once OS X reached v10.4 (Tiger) it became an architecturally complete, interesting and viable alternative which I'm very happy with as an ex-RISC OS user. While it has its fair share of faults, so does RISC OS. I just don't use my Risc PC or Iyonix for anything other than hobby development or ROOL work anymore.
I still wish operating systems routinely came with a "send to back" button and an option to avoid forcing a window to the front of the stack when focused! At least on Linux, RISC OS and OS X you can scroll windows which aren't frontmost (unlike on Windows) and on Linux and OS X you can move windows even when the application is busy or using blocking modal dialogue boxes (unlike Windows and RISC OS).
So where do I think this leaves RISC OS? For fun; for a hobby; for those few applications you have which you still really like. And ultimately, given a free OS from ROOL and a free emulator in the form of RPCEmu, what's so bad about that?