The latest version of Mono, the open source implementation of .NET for Unix, Windows, and other operating systems has been released - but it's not necessarily stable.
Mono 2.10 somewhat confusingly is the next release after 2.8 and, just as with that version, users who want stability are recommended to stick with Mono 2.6 - specifically version 2.6.7 - until Mono 3.0, the next "Long Term Supported" release, comes out.
For those who decide to take the "risky " route and upgrade to this version which, according to its Release Notes, has been released with features that "have not received as much testing as they should".
Top of the list of major highlights is support for Google's Native Client which allows developers to access the full capabilities of the client processor running native code in web applications while maintaining browser neutrality, OS portability, and security.
It introduces a new profiling engine which provides more information about heap and garbage collection activity and a faster socket stack. It also claims an improved parallel framework. Its new C# compiler backend can now use any custom mscorlib and its VB compiler can compile to both 2.0 and 4.0 profiles. The F# compiler and tools and the IronRuby and IronPython packages are now bundled with the Linux packages as well as in the Mac installer.
For the full details, check the detailed Mono 2.10 Release Notes
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Mono gets UI support