When viewing the text of the following feed : http://tweakers.mobi/rss/nieuws , you get the text of a comment instead of the text of the article.
I have the same problem on Windows Phone Central (http://www.wpcentral.com/). Sometimes, the article is replaced with a random comment, even though the text in the RSS feed is completly correct. Currently I encountered the problem with the article “How to set a location-based reminder with Cortana” (http://www.wpcentral.com/how-to-locat…). The RSS feed shows the article but NewsBlur shows the comment by Brent#WP: http://www.wpcentral.com/comment/8639…
Are you in Text view? Text view may inadvertently grab a comment, usually if its longer than the article and the original website has no semantic tagging or classnames like “.article” or “.story” or “.content” or the like. I use the industry standard: Readability. Everybody uses them and it works 99% of the time.
If you’re seeing comments where the rss feed should be, switch to Feed view, which displays only the rss feed. You can hit the text view temporarily for a single story by hitting “shift+enter” (and “enter” takes you to Story view temporarily).
Having the same issue with the Slashdot feed.