Thanks for taking the time to report this bug.
Without a stack trace from the crash it's very hard to determine what caused it.
Can you get us a stack trace? Please see http://live.gnome.org/GettingTraces for more information on how to do so. Thanks in advance!

Well I'm sorry but it doesn't work. Nautilus' just hanging when i hit prefences.. until I kill it.

This is all I can deliver:

(nautilus:13597): Eel-WARNING **: "unique eel_ref_str" hash table still has 5 elements at quit time (keys above)

--- Hash table keys for warning below:
--> file:///home

(nautilus:13597): Eel-WARNING **: "nautilus-directory.c: directories" hash table still has 1 element at quit time (keys above)
ingo@linux-myoq:~> nautilus
Initializing nautilus-gdu extension
Initializing nautilus-open-terminal extension

(nautilus:13604): GLib-GObject-WARNING **: specified class size for type `TrackerTagsView' is smaller than the parent type's `GtkVBox' class size

(nautilus:13604): GLib-CRITICAL **: g_once_init_leave: assertion `initialization_value != 0' failed
Killed


Nautilus' operating normally until 'Killed'
I'm gonna leave it hangin for a while, maybe it gives me a detailed error in advance.

(In reply to comment #2)

> (nautilus:13604): GLib-GObject-WARNING **: specified class size for type
> `TrackerTagsView' is smaller than the parent type's `GtkVBox' class size
> 
> (nautilus:13604): GLib-CRITICAL **: g_once_init_leave: assertion
> `initialization_value != 0' failed
> Killed

It looks to me that the Tracker extension you're using here is compiled against another GTK+ API than Nautilus, and this causes the hang.
Unless you manually installed Tracker or are using unofficial packages, this is a packaging bug of your distribution.

I'll keep an eye on it

I got it, after an uninstall of 'nautilus-extension-tracker-tags' everything is working fine. 

Checked on both machines, maybe this info can help somehow.