Pinging

Am I correct in the assumption that when you issue a new post to you blog in WordPress it automatically pings pingomatic.com?

If I uncheck the pinging box in the discussion section when writing a post will this turn off any automatic pingomatic ping feature?

If not, how do I go about disabling the pingomatic auto ping feature? Additionally, is their any way to default disable the pingomatic feature without disabling the ping feature that other blogs would utilize?

I want to utilize the http://pingoat.com/ site which covers more websites than pingomatic and I heard that pingomatic is sometimes not functioning properly due to overuse. If I can default disable pingomatic or uncheck the ping box will this cause any problems when I go to http://pingoat.com/ and ping their list of blog SE/Dir?

Lastly and the most simple route, if I just leave the pingomatic feature on and also utilize pingoat, some sites will be get pinged twice for the same post. Will I get in trouble for spaming?

Any imput on these questions is greatly appreciated. Thanks.