Steps to reproduce:
I enabled Audioscrobbler, configured it and played a song. After a while (I am guessing when it decides to upload data) it crashes.  

Banshee continued playing music, and it was importing my music library at the same time as well.

I quit Banshee ("Close" button on the error dialog), created the missing plugins directory, but after that Banshee would not start, either from Gnome menus or on a command line, until after I entered gconf-editor and disabled the Audioscrobbler plugin, and nuked my .gnome2/banshee directory.  The next time it crashed, I let it finish importing my music library, then created the plugins directory, and then Banshee loaded and audioscrobbler then worked without crashing.

Stack trace:
An unhandled exception was thrown: Could not find a part of the path "/home/reed/.gnome2/banshee/plugins".

at System.IO.FileStream..ctor (string,System.IO.FileMode,System.IO.FileAccess,System.IO.FileShare,int,bool,System.IO.FileOptions) <0x0022e>
at System.IO.FileStream..ctor (string,System.IO.FileMode,System.IO.FileAccess,System.IO.FileShare) <0x0001f>
at (wrapper remoting-invoke-with-check) System.IO.FileStream..ctor (string,System.IO.FileMode,System.IO.FileAccess,System.IO.FileShare) <0x0004b>
at System.Xml.XmlTextWriter..ctor (string,System.Text.Encoding) <0x0002a>
at Banshee.Plugins.Audioscrobbler.Queue.Save () <0x00061>
at Banshee.Plugins.Audioscrobbler.Engine.TransmitQueue () <0x00029>
at Banshee.Plugins.Audioscrobbler.Engine.StateTransitionHandler () <0x00175>
at (wrapper delegate-invoke) System.MulticastDelegate.invoke_bool () <0x0002c>
at TimeoutProxy.Handler () <0x0002a>
at (wrapper native-to-managed) TimeoutProxy.Handler () <0x0002b>
in (unmanaged) 0xa7ea7cf5
at (wrapper managed-to-native) Gtk.Application.gtk_main () <0x00004>
at Gtk.Application.Run () <0x00007>
at Banshee.BansheeEntry.Startup (string[]) <0x00657>
at (wrapper delegate-invoke) System.MulticastDelegate.invoke_void_string[] (string[]) <0x00037>
at Banshee.Gui.CleanRoomStartup.Startup (Banshee.Gui.CleanRoomStartup/StartupInvocationHandler,string[]) <0x000ae>

.NET Version: 2.0.50727.42

Assembly Version Information:

System.Web (2.0.0.0)
Mono.Security (2.0.0.0)
TagLib (0.0.0.0)
System.Configuration (2.0.0.0)
NotificationAreaIcon (0.11.2.17900)
MusicBrainz (0.11.2.17889)
MetadataSearch (0.11.2.17898)
MMKeys (0.11.2.17899)
Banshee.Plugins.Audioscrobbler (0.11.2.17897)
ipod-sharp-ui (0.0.1.0)
njb-sharp (0.3.0.37203)
Banshee.Dap.Njb (0.11.2.17896)
gnome-vfs-sharp (2.8.0.0)
Banshee.Dap.MassStorage (0.11.2.17895)
ipod-sharp (0.0.1.0)
Banshee.Dap.Ipod (0.11.2.17895)
GStreamerPlayerEngine (0.11.2.17894)
System.Xml (2.0.0.0)
System.Data (2.0.0.0)
Mono.Data.SqliteClient (2.0.0.0)
pango-sharp (2.8.0.0)
Mono.Cairo (2.0.0.0)
Hal (0.0.0.0)
Last.FM (0.0.0.0)
NDesk.DBus (0.0.0.0)
Mono.Posix (2.0.0.0)
Banshee.Widgets (0.11.2.17891)
glade-sharp (2.8.0.0)
gnome-sharp (2.8.0.0)
gconf-sharp (2.8.0.0)
NDesk.DBus.GLib (0.0.0.0)
gdk-sharp (2.8.0.0)
System (2.0.0.0)
atk-sharp (2.8.0.0)
glib-sharp (2.8.0.0)
gtk-sharp (2.8.0.0)
Banshee.Base (0.11.2.17894)
banshee (0.11.2.17901)
mscorlib (2.0.0.0)

Platform Information: Linux 2.6.16-1-686-smp i686 unknown GNU/Linux

Disribution Information:

[/etc/debian_version]
4.0



Other information: