MySQL bin log missing data?
You need to use the --base64-output=decode-rows and --verbose options with mysqlbinlog or you will not always see everything that's in the log.

You should also consider removing binlog_ignore_db from your configuration, because this not only prevents logging changes to the mysql schema, it also stops logging of events from your session that reference other schemas any time you USE mysql until you USE another database because of the way replication rules are interpreted.