All icons have disappeared

The latest update to 3.1 has made all the icons disappear for me, including from the settings page. Help!

The site in question is http://omexchange.com/ (although it is still working fine post-update on http://offgrid-festival.co.uk/ )

I’m guessing perhaps there is a plugin conflict? :-/

I’ve just copied my live site to the staging environment at http://omexchange.staging.wpengine.com and strangely, when I look at the JP Sharing setting page there I’m getting the following warning message:

Warning: Invalid argument supplied for foreach() in /nas/wp/www/staging/omexchange/wp-content/plugins/jetpack-sharing/sharedaddy/sharing-service.php on line 25

Weirdly enough I’m not getting this message on the live site, despite the exact same code being present.

I also just deactivated every single plugin apart from JP Sharing on the staging site and am still having the issue.

/me is baffled

Any ideas?

https://wordpress.org/plugins/jetpack-sharing/