Google at some point will probably come up with a way to filter out Blogg content that it deems "Spamish," but it would be impractical to think that Google will discount blogs altogether.
Some Bloggs are becoming more respected in their niche than many of major media conglomerates as a source reliable of information.
Pining your content, on your Blogg, to your RSS feed, on your Yahoo page has nothing to do with spam of any kind. Spam by definition is delivering a message or information to someone that doesn't want it and never requested it from you in first place.
Pinging your own information to yourself effects, harms, or inconveniences no-one. Thus will never can or will be considered spam.
Now on other hand if you are junk pinging snippets from pages on your site just to provide links for spiders to follow and index you pages faster and you are using services like "Ping-O-Matic" and blasting those feeds all over Internet, than you may cause yourself some problems.
The best practice to follow when blogging and pinging is to post complete content of a web page or article page, to ensure that post makes sense. Ask yourself if you visited your blog and read that post, would it make sense and offer some value to reader.