There is now a pre-packaged version of Inkscape running native on my MacPro under OS X 10.6.2. That's the good news. The bad news is that there's some more work needed to make it useable. On start up I get the following console messages:

Just to compare - these do not occur on my Tiger PPC build:

3/23/10 8:51:51 AM defaults[41485]
The domain/default pair of (kCFPreferencesAnyApplication, AppleAquaColorVariant) does not exist
3/23/10 8:51:51 AM defaults[41487]
The domain/default pair of (kCFPreferencesAnyApplication, AppleHighlightColor) does not exist
3/23/10 8:51:51 AM defaults[41496]
The domain/default pair of (.GlobalPreferences, AppleCollationOrder) does not exist

3/23/10 8:51:51 AM [0x0-0x606606].org.inkscape.Inkscape[41457] Warning: AppleCollationOrder setting not found, using AppleLocale.

3/23/10 8:51:51 AM [0x0-0x606606].org.inkscape.Inkscape[41457] (process:41460): Gtk-WARNING **: Locale not supported by C library.
3/23/10 8:51:51 AM [0x0-0x606606].org.inkscape.Inkscape[41457] Using the fallback 'C' locale.

These do occur on my Tiger PPC build as well:

3/23/10 8:51:51 AM [0x0-0x606606].org.inkscape.Inkscape[41457] cp: /Users/stu/inkscape_port/inkscape-0.47/packaging/macosx/stInkscape-aqua.app/Contents/Resources/etc/pango/pangox.aliases: No such file or directory

3/23/10 8:51:54 AM [0x0-0x606606].org.inkscape.Inkscape[41457] (inkscape-bin:41460): GLib-GObject-CRITICAL **: g_object_ref: assertion `object->ref_count > 0' failed
3/23/10 8:51:58 AM [0x0-0x606606].org.inkscape.Inkscape[41457] (inkscape-bin:41460): GLib-GObject-CRITICAL **: g_object_ref: assertion `object->ref_count > 0' failed
3/23/10 8:51:58 AM [0x0-0x606606].org.inkscape.Inkscape[41457] (inkscape-bin:41460): Gtk-WARNING **: Could not find the icon 'object-visible'. The 'hicolor' theme
3/23/10 8:51:58 AM [0x0-0x606606].org.inkscape.Inkscape[41457] was not found either, perhaps you need to install it.
3/23/10 8:51:58 AM [0x0-0x606606].org.inkscape.Inkscape[41457] You can get a copy from:
3/23/10 8:51:58 AM [0x0-0x606606].org.inkscape.Inkscape[41457] http://icon-theme.freedesktop.org/releases

3/23/10 8:54:15 AM [0x0-0x606606].org.inkscape.Inkscape[41457] (inkscape-bin:41460): Gtk-WARNING **: Unable to find default local directory monitor type
3/23/10 8:54:35 AM [0x0-0x606606].org.inkscape.Inkscape[41457] (inkscape-bin:41460): Gtk-WARNING **: Unable to find default local directory monitor type