Hi Guys,
I think the sentiments that is being passed here is the difference between link building and link earning... Submitting to directories is a link building activity that can be achieved with little friction, and therefore is often subcontracted to other people. But what are the directories? Will the ever be used to find a business like yours OR are they simply directory spam... My guess is the later.
There are a few directories out there that are worthwhile, but I would recommend making these submissions yourself. Set aside say 2hrs on a Saturday morning (OR Monday morning if it is simply the company you work for NOT own) to find the next one and make your submissions. I would take a top down approach to directory listings. Pick on the most beneficial and work your way down, continually asking yourself the question "Would I use a site like this to find a business like mine?"
If you are in the States, Canada OR UK I would suggest looking into getListed.org (Please getListed/SEOMoz team, do Australia next
for directories worth chasing. Also SEOMoz have a list of directories that they feel are worthwhile that you can access as a PRO user... Some are genre directories.
Think about it this way, What happens if your company was to move? Running directory listings on 100, 500, 1000 poor quality directories, would you bother to update the address on all of them. If you got someone else to do it, would you have all the login details they used to generate all these links... Probably not... If you do it yourself, you have all the details, you have only approached the directories worth targeting and the task is a lot more manageable...
Running low quality backlinks (directory listings included) puts you at greater risk of the Penguin update. Once you have sit below the threshold, you are at risk of being penalised either manually or by the next Penguin update. Mpst SEO will tell you, the recovery tasks involved in breaking the Penguin penalty are 2 to 5 times the amount of work that building the poor links in the first place. Don't risk it!
On a final note, link earning is about chasing after those links that have the friction associate to them to acquire... EG/ Google Maps with there postcards approval process etc. You should always approach any form of backlink by believing the link will be more valuable from the organic traffic that it will bring your site from the source site than the backlink is towards your backlinking profile.
Thus ends my novel, congrats if you made it this far 
Hope this helps,
Dan