Hi Greg,
First of all many thanks for this plugin, I just left All in SEO for yours to fix an incredible CPU usage I have had with the former one.
However I cannot fix a problem with GHP SEO:
Sometimes keywords entered in Head Keywords fields are not visible when I return to modify page/post after saving or duplicate. Note that they are correctly saved in _ghpseo_keywords in postmeta table. I already increase suhosin vars biut doesn't fix it. Of course "Enable Keywords on Writing/Editing Screens" is ON. Any idea ?
http://wordpress.org/extend/plugins/gregs-high-performance-seo/