As DocType says you definitely want to make sure your site is ‘functional’ and free of errors before you start pinging the SE’s. If you let the SE’s know your site is ‘alive’ or has updated content and it’s full of errors, it’s going to index this and make a note of it. If it’s real bad you may have your site dropped out of the index.
Pinging is useful only if you have your site optimized before you ping it.
Think about it, if your site “as is” only rates a zero on Google’s PR scale, then it does you little good to have it indexed, because it’s still going to be buried 10 pages down the SERP’s.
In order to let our website/blog information know to search engines and other website we do pinging. As SE’s crawl every online information to find relevant results for us, we follow this method to notify them that our website/blog exists at specific place. There are various resource available that can ping our data to various search engines.
Pinging will let the search engines know that you put something new on your site - and they’ll index it faster.
However, pinging doesn’t do anything to help drive up your traffic. For that, you’ll have to stick with good ol’ fashioned SEO. Promote your blog - do some guest blogging, post on forums relevant to your niche, do some article marketing. All of it will go towards getting you a higher search engine ranking, which WILL increase your traffic.