I discovered a new bug that was introduced in 10.8.3 - it happens when managing iCloud documents using Numbers' "New" or "Open" windows. If I will drag some document to Trash (or do the same from the context menu) - the document will be deleted but won't appear in Trash! I've noticed that some "recovered" files appeared in Trash after a reboot - it was a folder with tiff thumbnail of the document but not the deleted document itself. Same thing happens on both my MacBook Pro (13'', retina, late 2012) and Mac mini (mid-2012). Both were on 10.8.2 and upgraded to 10.8.3 through App Store. Reinstall of Numbers did not help.