At Josh Andler's request, I tried copying the new files from GTK+ site (
http://www.gtk.org/download-windows.html) over the old devlibs, overwriting all duplicates. (To try and see if this would sort out something with graphics tablets.) It failed in linking.
mingw32-g++ -o build/inkscape.exe -mwindows -mthreads build\inkres.o build\obj\main.o build\obj\winmain.o build\libinkscape.a -Lc:/devlibs-new-gtk/lib -Lc:/devlibs-new-gtk/lib -lpoppler -Lc:/devlibs-new-gtk/lib -lpoppler-glib -Lc:/devlibs-new-gtk/lib -lgobject-2.0 -Lc:/devlibs-new-gtk/lib -lglib-2.0 -lintl -Lc:/devlibs-new-gtk/lib -lgdk-win32-2.0 -Lc:/devlibs-new-gtk/lib -lgdk_pixbuf-2.0 -Lc:/devlibs-new-gtk/lib -lpangowin32-1.0 -lgdi32 -Lc:/devlibs-new-gtk/lib -lpango-1.0 -Lc:/devlibs-new-gtk/lib -lpangocairo-1.0 -Lc:/devlibs-new-gtk/lib -lcairo -Lc:/devlibs-new-gtk/lib -lpoppler -Lc:/devlibs-new-gtk/lib -lgtkmm-2.4 -Lc:/devlibs-new-gtk/lib -lglibmm-2.4 -Lc:/devlibs-new-gtk/lib -lgobject-2.0 -Lc:/devlibs-new-gtk/lib -lglib-2.0 -lintl -Lc:/devlibs-new-gtk/lib -lsigc-2.0 -Lc:/devlibs-new-gtk/lib -lgdkmm-2.4 -Lc:/devlibs-new-gtk/lib -lpangomm-1.4 -Lc:/devlibs-new-gtk/lib -lpango-1.0 -Lc:/devlibs-new-gtk/lib -lpangocairo-1.0 -Lc:/devlibs-new-gtk/lib -lcairo -Lc:/devlibs-new-gtk/lib -lgdk-win32-2.0 -Lc:/devlibs-new-gtk/lib -lgdk_pixbuf-2.0 -Lc:/devlibs-new-gtk/lib -lpangowin32-1.0 -lgdi32 -Lc:/devlibs-new-gtk/lib -lcairomm-1.0 -Lc:/devlibs-new-gtk/lib -latkmm-1.6 -Lc:/devlibs-new-gtk/lib -latk-1.0 -Lc:/devlibs-new-gtk/lib -lgtk-win32-2.0 -Lc:/devlibs-new-gtk/lib -lgdk-win32-2.0 -Lc:/devlibs-new-gtk/lib -lgio-2.0 -Lc:/devlibs-new-gtk/lib -lpangoft2-1.0 -Lc:/devlibs-new-gtk/lib -lpango-1.0 -Lc:/devlibs-new-gtk/lib -lglib-2.0 -lintl -Lc:/devlibs-new-gtk/lib -lfreetype -Lc:/devlibs-new-gtk/lib -lfontconfig -Lc:/devlibs-new-gtk/lib -lgthread-2.0 -Lc:/devlibs-new-gtk/lib -lglib-2.0 -lintl c:/devlibs-new-gtk/bin/libxml2.dll c:/devlibs-new-gtk/bin/libxslt.dll -Lc:/devlibs-new-gtk/lib -lcairo -Lc:/devlibs-new-gtk/lib -lcairomm-1.0 -Lc:/devlibs-new-gtk/lib -lcairo -Lc:/devlibs-new-gtk/lib -lwpg-0.1 -Lc:/devlibs-new-gtk/lib -lwpd-0.8 -Lc:/devlibs-new-gtk/lib -lwpg-stream-0.1 -Lc:/devlibs-new-gtk/lib -lwpd-0.8 c:/devlibs-new-gtk/lib/iconv.lib -Lc:/devlibs-new-gtk/lib -lMagick++ -Lc:/devlibs-new-gtk/lib -lWand -lMagick -Lc:/devlibs-new-gtk/lib -lfontconfig -Lc:/devlibs-new-gtk/lib -lfreetype -lssl -lcrypto -Lc:/devlibs-new-gtk/lib -llcms -Lc:/devlibs-new-gtk/lib -lgsl -lgslcblas -lm -lpng -ljpeg.dll -ltiff.dll -lpopt c:/devlibs-new-gtk/lib/zdll.lib -lgc -lws2_32 -lintl -lgdi32 -lcomdlg32 -lm -lgomp -lpthreadGC2 -laspell
(Whew, copied that out by hand... well, not quite :P)
Make error line 469: LINK problem: c:/devlibs-new-gtk/lib/libpoppler-glib.a(CairoFontEngine.o):c:\dev\poppler\poppler-0.8.4\poppler/CairoFontEngine.cc:225: undefined reference to `cairo_ft_font_face_create_for_ft_face'
collect2: Id returned 1 exit status
Obviously this isn't good. What should I do next? I figure that I need to update poppler (it's way out of date too) to match with the new version of Cairo with the GTK package (1.8.8). However there aren't any build instructions for it. I'll see if I can work it out (using the cmake gui I'm up to it needing FreeType), but anyway, I just thought I'd tell you :-)