Personally, I hate those purple bookmark icons. They draw too much attention in my favorites bar. I prefer the more subtle look of the graphite version, but don't want to use graphite appearance globally.
In case anyone else feels this way, I thought I'd share a little terminal command I run to replace the purple one with a copy of the graphite one:
Code:
cp -f /Applications/OmniWeb.app/Contents/Frameworks/OmniHTML.framework/Versions/A/Resources/OHZapGraphite.png /Applications/OmniWeb.app/Contents/Frameworks/OmniHTML.framework/Versions/A/Resources/OHZap.png
That's all one line.
Disclaimer: this works for me, but I assume no responsiblity for any damage you might cause to your system due to this post. YMMV.