I suppose pinging might improve indexing speed, but left to their own devices they are indexed very rapidly indeed. I don't understand the trend with regards to hubs, though I do for blogs, where it can take some time otherwise.
I wouldn't bother. Pinging might mean indexing takes hours, not pinging might mean a day. Not worth the effort.
Pinging is just a way of letting the search engines know that you've updated your blog. Search engines like new content so hopefully this will get your site indexed quicker.
I usually use ping-o-matic for this but I do know that there several different ones that you can use. When you get to the site just put in your blog name and URL then check off the services that you want to ping and that's all there is to it.