In my own experiences, submitting to directories would be not so effective as it used to be though it would still be helpful for increasing link popularity purpose since your could not setup correct anchor text using your targeted keywords.
all the best,
I would say choose your Niche carefully make a list of 20 best Directory in your Niche and Submit. Submitting in good related directories still have good values. and also consider submitting some good Local Directories along with all the big names, locals are good source of quality traffic too.
There's no point on submitting your sites on thousands of directories as it won't help you get backlinks as most of the link that's are approved by these sites are not indexed by google.I myself have tried it and got no good response, in place of this you can try some good 20 to 30 paid directory of your niche.
No it's not useless, point is very few of them gets approved you can do one thing make a list of all those directories on which your site get's approved for future use also make sure they are indexed in google. Yes there are some good paid directories like avivadirectory.com which are manually approved which can help you build some good backlinks.
I've had such difficult time finding a value to directory submissions, I've done so many and they haven't even produced one air of usefulness. I've probably submitted my website to hundreds with no value added. Directory submissions are such a scam! Uggh, don't even pay for it either, waste, I assure you!
I also think that Directory submission has its own place in link building,and there is no true in saying that it is a waste of time.As far as traffic is concerned it might be specialty of high PR directories,they really are the source of traffic but low PR directories also help your sites getting it weight, when spider finds your link in these directories while crawling.
Link building is similar to the idea of building your reputation to the public. If you have 1000 people who basically have very little ability to improve your image by just knowing you (let's call them people with a PR of 0), your reputation is out there with 1000 people. If any of those people become better in terms of their ability to improve your image, your reputation potentially could increase, but the liklihood is low. However, if Oprah (PR 10) comes along and says you're the best writer, your reputation increases quite a bit. Your value becomes very strong as well.
You shouldn't stop building up your network of relationships with all those people who don't have much of an ability to hurt/help your relationship, but it does help to build relationships with people who can help you in your industry or developing higher valued connections.
SEO's have been doing it for quite some time though. Check out this post (especially the comments). You'll see Aaron Wall (the SEO Book guy) saying it "was" effective in 2006 for him.
It might not be returning as much value these days as it did in the past when it was a competitive advantage in the early days of SEO. I wouldn't say it's worthless, but you should think about how to spend your time since there's SO many distractions online.
Directory submission is the basic activity for any website in seo process. I think they are effective and good source of collecting one way link for the site. It helps when it done in quality directories.