I'm beating a very, very, very dead horse by this point so it should come as no surprise to anyone that OSNews has this thing for BeOS. Most of the long-lasting team members, although currently under varying levels of inactivity, all have a history with BeOS. Even OSNews itself can be seen as a sprout of BeNews, taken under her wring by Eugenia after she left BeNews. Adam, our webmaster and programmer of the current site, was a BeOS user back in the day, and I, too, come from a BeOS world.
So, yes, every Haiku release is a bit special over here. Also, you really should read the first two pages of my Haiku R1 alpha 1 review, titled "In the round".
This one fixes a lot of bugs - well over a 1000 bugs were squashed, including about a 100 more subtle ones uncovered through Coverity scanning. Furthermore, Haiku should be more pleasant to use in a modern environment thanks to things like WPA/WPA2 support, improved generic and video drivers, better CPU support, and so on. A pcnet network driver should make it easier to run Haiku in VirtualBox.
Furthermore, a new version of WebKit is included which should improve browsing with WebPositive. IPv6 modules have been added, as well improvements to the BFS file system, including better error detection and correction and support for very large disks and partition (more than 63TB).
Going even nittier and grittier, debugging has been improved thanks to new KDL tools, and native debugger application for applications. POSIX support has been improves, including real-time extensions, and the experimental compiler has been updated to GCC 4.6.3. The OpenGL kit has been updated to Mesa3D 7.8.2.
Due to the alpha nature of the release, there's a list of known issues, so before you run out and install this, be sure to read the release notes properly. As always, the Haiku source code is freely available.