Are there any releases for Linux ?
tarball is all you need to use / install Mono on Linux. If you want your favorite distribution to import this version of Mono into your packaging system (for example, apt-get), you will need to ask on forums, mailing lists, or other online resources about this distribution.
Are there any releases for Windows ?
First, I will ask you another question: are you sure that you really need Mono for Windows? In most cases, Windows already associates .NET with the latest versions. In addition, Mono for Windows is not the main platform for the Mono team, and may lack features or have worse performance than on Linux / Mac. Therefore, Mono for windows is really very useful for some unusual scenarios .
If you are really interested in such unusual use cases, continue to listen to Mono accompaniment on your forums, mailing lists or IRC to remind them of their packaging (this is no longer a priority since this platform is not one with their commercial offers ).
UPDATE : A Xamarin employee stated that the installer will be available when version 3.2.3 is released and they have kept their promise since version 3.2.3 was released and the Windows installer is available on the download page.