Progress has been slow, but impressive. For Linux and FreeBSD on the x86, AROS is mostly working and there are builds for Linux on 680X0 and native Amigas. The Amiga and 680X0 Linux flavours feature binary compatibility (a list of software which has been tested and known to work is published on the website), and all versions support fully-functional Intuition windows.
In addition, a standalone x86 version is in the works (thanks to the effort of Michael Schulz), which promises to be an ideal showcase of what AROS has achieved. The version currently boots into the Amiga's internal debugger, SAD, so doesn't support much in the way of software, but once the appropriate hardware drivers are implemented it will be a fully functioning AROS/Amiga platform running on standard PC compatible hardware. The same can be done for pretty much any other hardware out there - the only reason why other such ports haven't materialised is lack of support. If any developer out there fancies helping AROS port to such platforms as PowerPC (PowerUP and/or CHRP), there has never been a better time to get involved - AROS on G4 anyone?
Take a look at the screenshots on the AROS site to get the general idea (URL listed at the base of the article) or download the source and binaries for a real hands-on peek. (Unfortunately, the AROS FTP site is currently unavailable but should be up again shortly)