I’ve written a small Python script which uses the excellent boto libraryto monitor Beanstalkd server statistics as well as a specific beanstalkd tube (queue) statistics.

You can get the code here: https://github.com/erans/beanstalkdcloudwatch
The easiest way to run it is via a cron job. I run it every 1 minute to monitor the “reserved” and “buried” state of a few of the tubes I use (if you want to read more about how beanstalkd works I suggest reading the protocol document).
I highly recommending checking beanstalkd out if you need a queue for offloading tasks to other processes/machines. It’s really geared towards that task and have a couple of dedicated features such as the buried state, time-to-live and time-to-run which makes managing this really painless.