I can ping everything now.
Okay, not everything, but at least www.weblogs.com and blo.gs.
I already had some of the code in place, but then I came across an example by Charles Cook, mr. xml-rpc.net hisself, and decided to hack it a little bit. Pretty simple stuff, but this post will tell me if it works :)
/me:crosses fingers
update:
So it looks like it "kinda" worked for weblogs.com - since my blog engine, .Text pings weblogs.com itself, I got a nice little message from weblogs.com saying I should get out more and enjoy life for pinging twice in a row. Well, my friends, it's raining today. blo.gs came back saying that the server returned invalid xml.
Oh well, guess I'll try again on Monday :)