diff -Naur shotwell-0.7.2-orig/src/PhotoExporter.vala shotwell-0.7.2-new/src/PhotoExporter.vala
--- shotwell-0.7.2-orig/src/PhotoExporter.vala	2010-09-10 19:55:55.000000000 -0300
+++ shotwell-0.7.2-new/src/PhotoExporter.vala	2010-10-10 17:53:07.000000000 -0300
@@ -1,9 +1,21 @@
-/* Copyright 2010 Yorba Foundation
+  /* Copyright 2010 Yorba Foundation
  *
  * This software is licensed under the GNU Lesser General Public License
  * (version 2.1 or later).  See the COPYING file in this distribution. 
  */
 
+
+// This is used to enumerate the photos with same timestamp
+class DateTimePhotoItem {
+  public int next;
+  public Photo? orig;
+
+  public DateTimePhotoItem(int next, Photo? p) {
+    this.next = next;
+    this.orig = p;
+  }
+}
+
 public class PhotoExporter : Object {
     public enum Overwrite {
         YES,
@@ -120,12 +132,61 @@
             export_completed();
     }
     
+    
+
+
     private bool process_queue() {
         int submitted = 0;
+        ///*
+        //These are used to check if a basename has already been used and to
+        //map a photo to a new basename on the expor folder
+        var datetimes = new Gee.HashMap<string,DateTimePhotoItem> ();
+        var name_map = new Gee.HashMap<Photo,string> ();
+
+        // First Pass -- Maps photos to names
+        // I1'm mapping from name -> YYYY:MM:DD HH:MM:SS(-seq)?.jpeg
+        // That's arbitrary, but is there any sense in exporting a selection
+        // and keeping the original names that make no sense in the exported
+        // directory?
+
+        AppWindow.get_instance().set_busy_cursor();
+
+        int seq_digits = (int)(GLib.Math.log10(photos.size)) + 1;
+        
         foreach (Photo photo in photos) {
-            string basename = photo.get_export_basename(file_format);
+            string datetime =
+              photo.get_metadata().get_digitized_date_time().get_exif_label();
+            string destname;
+
+            if (datetime in datetimes) {
+              DateTimePhotoItem d = datetimes[datetime];
+
+              if (d.next == 2) {
+                // First duplicate
+                // Needs to rename the original file, to keep consistency
+                string destname_orig = "%s-%0*d".printf(datetime,seq_digits,1);
+                name_map[d.orig] = destname_orig;
+              }
+
+              destname = "%s-%0*d".printf(datetime,seq_digits,d.next);
+              datetimes[datetime].next = d.next++;
+
+            } else {
+              destname = "%s".printf(datetime);
+              // store the next sequence number: this is 1, next is 2
+              DateTimePhotoItem d = new DateTimePhotoItem(2,photo);
+              datetimes[datetime] = d;
+            }
+
+            name_map[photo] = destname;
+
+        }
+
+        //*/
+        foreach (Photo photo in photos) {
+            string basename = file_format.get_default_basename(name_map[photo]);
             File dest = dir.get_child(basename);
-            
+
             if (!replace_all && dest.query_exists(null)) {
                 switch (overwrite_callback(this, dest)) {
                     case Overwrite.YES:
@@ -220,6 +281,8 @@
     }
     
     private bool on_export_failed(PhotoExporter exporter, File file, int remaining, Error err) {
+        stdout.printf("Exception on export: %d, %s\n",err.code,
+        err.message);
         return export_error_dialog(file, remaining > 0) != Gtk.ResponseType.CANCEL;
     }
 }