Il recente (ieri) upgrade Jetpack 2.2.3 aveva problemi se installato con bbpress.
Sono stato uno dei primi a segnalarlo nel forum Warning: Invalid argument supplied for foreach() in /home/culturet/public_html/wp-content/plugins/jetpack/jetpack.php on line 4534
Io per risolvere il problema feci un roll back alla versione 2.2.2 di Jetpack.
Questa mattina già pronta la versione Jetpack 2.2.4 che risolve ogni problema con giustificazione e scuse!
I want to apologize, firstly, for pushing multiple updates out to you in one day. We’ve been doing our very best over the last several months to make sure that our releases are stable and tested in as many disparate environments as possible.
In this case, a bug cropped up because of an oversight in how we loaded a compatibility file for bbPress in Jetpack. It wasn’t caught in testing, which is unfortunate. This is a good example, though, of how we learn from our mistakes, improve our processes, and do better with the next release.
For those users effected by this, we decided it would be better to release Jetpack 2.2.4 as soon as possible to resolve this issue.