Wpburner is an automated blog and ping service. They have lots of WordPress blogs set up they crawl your site and post links to your pages on their blogs. You just put in the domain and how many pages you want crawled and you are done.
A lot of their blogs have been around for a while, so they have link popularity (or PageRank for you that still like it). Getting some external links from their popular blogs must help along with the blog and ping process. The downside is that it can get expensive if you B&P lots of pages.
I’ve seen some people swear by it and some saying it doesn’t work as well as traditional blog and ping. Personally I use them and let them crawl 50-100 pages from each new site. As for my results they have been good so far but I don’t have enough data to say WPburner is definitely good.
If you don’t have time to do blogging and pinging yourself, give them a spin. You might be surprised.