I start rhythmbox with the -d option and output all debugging information to a
file. Then I load my music library. It will read some of it and then just stop
with the "Loading Songs..." bar still pulsating. It never continues to scan the
rest of my collection.

Here is part of the output from the last folder it successfully scans:

[0x81e37c0] [rb_metadata_gst_load_tag] rb-metadata-gst.c:361 (12:58:41): uri:
file:///mnt/160GB/music_cds/Super%20Mario%20RPG/113%20Explanation!.mp3 tag: artist
[0x81e37c0] [rb_metadata_gst_load_tag] rb-metadata-gst.c:361 (12:58:41): uri:
file:///mnt/160GB/music_cds/Super%20Mario%20RPG/113%20Explanation!.mp3 tag: album
[0x81e37c0] [rb_metadata_gst_load_tag] rb-metadata-gst.c:361 (12:58:41): uri:
file:///mnt/160GB/music_cds/Super%20Mario%20RPG/113%20Explanation!.mp3 tag: date
[0x81e37c0] [rb_metadata_gst_load_tag] rb-metadata-gst.c:361 (12:58:41): uri:
file:///mnt/160GB/music_cds/Super%20Mario%20RPG/113%20Explanation!.mp3 tag: comment
[0x81e37c0] [rb_metadata_gst_load_tag] rb-metadata-gst.c:361 (12:58:41): uri:
file:///mnt/160GB/music_cds/Super%20Mario%20RPG/113%20Explanation!.mp3 tag:
track-number
[0x81e37c0] [rb_metadata_gst_load_tag] rb-metadata-gst.c:361 (12:58:41): uri:
file:///mnt/160GB/music_cds/Super%20Mario%20RPG/113%20Explanation!.mp3 tag: genre
[0x81e37c0] [rb_metadata_gst_load_tag] rb-metadata-gst.c:361 (12:58:41): uri:
file:///mnt/160GB/music_cds/Super%20Mario%20RPG/113%20Explanation!.mp3 tag: duration
[0x81e37c0] [rb_metadata_gst_load_tag] rb-metadata-gst.c:361 (12:58:41): uri:
file:///mnt/160GB/music_cds/Super%20Mario%20RPG/113%20Explanation!.mp3 tag: bitrate
[0x81e37c0] [rb_metadata_gst_load_tag] rb-metadata-gst.c:361 (12:58:41): uri:
file:///mnt/160GB/music_cds/Super%20Mario%20RPG/113%20Explanation!.mp3 tag: layer
[0x81e37c0] [rb_metadata_gst_load_tag] rb-metadata-gst.c:361 (12:58:41): uri:
file:///mnt/160GB/music_cds/Super%20Mario%20RPG/113%20Explanation!.mp3 tag: mode
[0x81e37c0] [rb_metadata_gst_load_tag] rb-metadata-gst.c:361 (12:58:41): uri:
file:///mnt/160GB/music_cds/Super%20Mario%20RPG/113%20Explanation!.mp3 tag: emphasis
[0x81e37c0] [rb_metadata_gst_fakesink_handoff_cb] rb-metadata-gst.c:437
(12:58:41): in fakesink handoff
[0x81e37c0] [rhythmdb_entry_new] rhythmdb.c:730 (12:58:41): emitting entry added
[0x81e37c0] [rb_metadata_load] rb-metadata-gst.c:469 (12:58:41): loading
metadata for uri:
file:///mnt/160GB/music_cds/Super%20Mario%20RPG/114%20A%20New%20Partner.mp3
[0x81e37c0] [rb_metadata_gst_typefind_cb] rb-metadata-gst.c:422 (12:58:41):
found type application/x-id3
[0x80e25b8] [rb_shell_clipboard_entryview_changed_cb] rb-shell-clipboard.c:556
(12:58:41): entryview changed
[0x80e25b8] [rb_shell_clipboard_sync] rb-shell-clipboard.c:364 (12:58:41):
syncing clipboard
[0x80e25b8] [rb_shell_player_entry_view_changed_cb] rb-shell-player.c:1515
(12:58:41): entry view changed
[0x80e25b8] [rb_shell_player_sync_buttons] rb-shell-player.c:1684 (12:58:41):
syncing with source 0x8229a20
[0x80e25b8] [rb_shell_player_set_play_button] rb-shell-player.c:1577 (12:58:41):
setting play button
[0x80e25b8] [rb_statusbar_entry_view_changed_cb] rb-statusbar.c:582 (12:58:41):
entry view changed
[0x80e25b8] [rhythmdb_query_model_poll] rhythmdb-query-model.c:902 (12:58:41):
inserting 1 rows
[0x80e25b8] [rb_entry_view_row_inserted_cb] rb-entry-view.c:1736 (12:58:41): row
added
[0x80e25b8] [queue_changed_sig] rb-entry-view.c:1669 (12:58:41): queueing
changed signal
[0x80e25b8] [rhythmdb_query_model_poll] rhythmdb-query-model.c:902 (12:58:41):
inserting 1 rows
[0x80e25b8] [rb_entry_view_row_inserted_cb] rb-entry-view.c:1736 (12:58:41): row
added
[0x80e25b8] [rhythmdb_query_model_poll] rhythmdb-query-model.c:902 (12:58:41):
inserting 1 rows
[0x80e25b8] [rb_entry_view_row_inserted_cb] rb-entry-view.c:1736 (12:58:41): row
added
[0x80e25b8] [paned_size_allocate_cb] rb-library-source.c:1150 (12:58:41): paned
size allocate
[0x80e25b8] [paned_size_allocate_cb] rb-shell.c:2530 (12:58:41): paned size allocate
[0x80e25b8] [paned_size_allocate_cb] rb-library-source.c:1150 (12:58:41): paned
size allocate
[0x80e25b8] [paned_size_allocate_cb] rb-shell.c:2530 (12:58:41): paned size allocate
[0x80e25b8] [rb_shell_player_state_changed_cb] rb-shell-player.c:1435
(12:58:41): state changed
[0x80e25b8] [rb_shell_player_sync_control_state] rb-shell-player.c:1377
(12:58:41): syncing control state
[0x80e25b8] [rb_shell_player_sync_buttons] rb-shell-player.c:1684 (12:58:41):
syncing with source 0x8229a20
[0x80e25b8] [rb_shell_player_set_play_button] rb-shell-player.c:1577 (12:58:41):
setting play button
[0x80e25b8] [rb_library_source_state_pref_changed] rb-library-source.c:1174
(12:58:41): state prefs changed
[0x80e25b8] [rb_library_source_state_prefs_sync] rb-library-source.c:1158
(12:58:41): syncing state
[0x80e25b8] [rb_library_source_state_pref_changed] rb-library-source.c:1174
(12:58:41): state prefs changed
[0x80e25b8] [rb_library_source_state_prefs_sync] rb-library-source.c:1158
(12:58:41): syncing state
[0x80e25b8] [rb_shell_player_state_changed_cb] rb-shell-player.c:1435
(12:58:41): state changed
[0x80e25b8] [rb_shell_player_sync_control_state] rb-shell-player.c:1377
(12:58:41): syncing control state
[0x80e25b8] [rb_shell_player_sync_buttons] rb-shell-player.c:1684 (12:58:41):
syncing with source 0x8229a20
[0x80e25b8] [rb_shell_player_set_play_button] rb-shell-player.c:1577 (12:58:41):
setting play button
[0x80e25b8] [paned_changed_cb] rb-shell.c:2550 (12:58:41): paned changed
[0x80e25b8] [rb_shell_sync_paned] rb-shell.c:2508 (12:58:41): syncing paned to 196
...etc