Update while waiting for the new article.
IE9 refuses to open the http page.
Chrome displays it as text.
Firefox opens it properly.
The last one I know I got for sure is the Ask Developer one.
This one has a weird character near the end, between the two <br/> things. Seems like some rss viewers can handle it, some don't.
Ok, new news article appeared as it should in Outlook, and the oldest article is removed from the webfeed. So the next news article should propably repair the feed for those of you who still have trouble :/