Since the developers deliberately broke the very useful emblems feature that I've relied on for years and years with Ubuntu ( How do I tag files with custom icons in Nautilus? ), while offering no replacement whatsoever, I guess I need to revert to the older version of Nautilus. How can I do this?
Nautilus in oneiric requires the GTK+3 libraries whereas Nautilus in Natty requires the GTK+2 libraries - quite different.
I'm afraid this will not be easily possible - you will need to recompile and probably have to do major code surgery... it's far easier just to stay with 11.04 if this emblem function is a major capability you require until a Gnome 3 alternative is developed.
Please see this Q&A for a scripted workaround:
The new Nautilus is part of the gnome 3 software bundle, while the old nautilus was part of gnome 2. So I guess it is not the fault of the ubuntu developers. Some changes from gnome 2 to gnome 3 cannot easily be understood and complicate the workflow imho. Maybe there is an extension for nautilus somewhere to attach the icons.
EDIT: Ok I found an explanation here on askubuntu: How do I tag files with custom icons in Nautilus?
The Gnome developers simply removed this feature and here is an explanation by the gnome developer team. http://mail.gnome.org/archives/nautilus-list/2010-July/msg00023.html
Sorry that there is nothing more to do right now, but I guess someone will design a nautilus-extension for customizing icons with emblems.
This feature is not useful to the majority of people, but it does add UI elements that clutters the experience. That's why it should be implemented as a plugin so that the relatively few people who wants it, can have it without bothering the majority. The freedom to tailor your software to suit your specific needs, is what makes open source a very friendly way of satisfying all needs. You really wouldn't want to have hundreds of dialogs installed by default in order to suit all potential use cases.
And before you start complaining that nobody has written that plugin for you yet, please keep in mind that Ubuntu 11.10 has not been released. Ubuntu 10.04 is supported until April 2013. 11.04 is supported until October next year. There is plenty of time to fix this before you need to upgrade.