Thanks for taking the time to provide this update - very helpful.
I'll just add a couple of ping services for EC members to consider. I use these to ping each new Web Bizz Blog post I make:
These services will ping numerous sites, as you will see. Generally, I use the first one, taking note of which pings were successful; then ping the second site, sending pings only to those not covered in the first site; then do the same with the third one.