See also Orca bug #538390, which is blocked by this issue.
http://bugzilla.gnome.org/show_bug.cgi?id=538390

Steps to reproduce:

1. Start Orca. Enable echo by word if it's not already enabled.

2. Launch Impress and create a new blank presentation.

3. Type Alt-v to bring up the View menu, and check: View menu -> Outline

3. Create new slides by typing multi-word titles and pressing Return.

Expected results:  Orca would echo each word typed.
Actual results: Orca is silent.

4. While typing a title, use backspace and/or delete.

Expected results: Orca would speak the character which was deleted.
Actual results: Orca is silent.

5. Use Up/Down/Left/Right to review the text in the outline.

Expected results: Orca would speak the line/character moved to.
Actual results: Orca is silent.

Orca is not getting any accessibility events from simpress. See the
end of the Orca debug log attached to the Orca bug:
http://bugzilla.gnome.org/attachment.cgi?id=112844&action=view

This was tested against OOo 3.0beta_2008-429 (on Ubuntu Hardy).