Everything comes to an end. Even support for MSVC6, a.k.a. Microsoft Visual Studio 98, which subtly hints at just exactly how old this compiler was. I wouldn't be surprised if wxWidgets were the last open source library to still support it 15 years after its initial release but now, finally, it's over and 3.2 release will require just barely ten year old MSVC7 or maybe even MSVC8 if nobody uses VC7 any more (but up to at least a year ago, some people were still actually using VC6, which is why it was, and remains, still supported in 3.0 release, although with quite some functionality not available for it).
In addition to dropping support for VC6, which was the really important change as it means we can, finally, write the code in wxWidgets itself in something resembling standard C++, we also officially stopped supporting Windows 9x (95/98/ME) in wxMSW port. Windows XP remains supported however as the differences between it and later Windows versions are much smaller than those with Win9x.
Finally, another port bites the dust: this time it was wxPM, the port of wxWidgets to OS/2. As far as I know, neither the port nor the platform itself are used since quite some time and the last real contribution to it dates from almost 5 years ago.
Edit: I am on a tear, since writing the initial version of this post, I've also removed support for the obsolete OpenWatcom and DigitalMars compilers as well as positively ancient (last century) MinGW versions. At this rate, there will be nothing left to remove soon, so I am going to really stop now.
All in all, a good day of work:
% git diff --shortstat master@{yesterday} 1756 files changed, 12868 insertions(+), 190758 deletions(-)