for automatic, i can't guaranty, but for manual there's a change to get your website to higher traffic and ranking on google and alexa,
In my opinion it absolutely does work, but from my position everything that a "paid submission service" does can be done free with a little work on your part.
Automatic directory submission is a bad idea, and could end up getting you penalized. You want to evaluate each and every single site you submit to, to ensure that the directories you'll be in are all on seperate IPs (and in my experience, they won't be) and that they only allow quality sites in them. Goolge has severely damped the juice that directories pass on, so you'll want to pick out only the best ones to submit to. and many of these 'directory networks' that are out there have been flagged as 'bad neighborhoods' by google, and should be avoided.
I always pay for manual directory submission and manual social bookmarking submission and it really helps me with traffic.