How well does Ping.fm parse Wordpress blog feeds?

How well does Ping.fm parse Wordpress blog feeds?  It depends on how you look at it, and how long you look at it.  With a statistically insignificant number of samples . . . a grand total of two . . . I'll give the optimistic view of Ping.fm's performance, and give it the benefit of the doubt by saying it got exactly half right. The other half, not so good.

Background:

"The WordPress->Feedburner->Ping.fm did not work any better than the Blogger->Feedburner->Ping.fm did. Maybe the problem is with Feedburner. I just switched to the native WordPress feed of this blog to Ping.fm, just to see what happens next." 

- The Learning Curve - RSS to Ping.fm - Again

The first and most encouraging sample was Ping.fm-feed version of this Wordpress post: Another Ping.fm test

Ping.fm correctly came up with this as its shortened link: http://ping.fm/8m1Jo

The second less than inspiring example is Ping.fm's rendition of #smartmarket test

For this one, Ping.fm came up with a shortened link, http://ping.fm/6D8ie, that incorrectly re-directed to the blog post's comment feed:

feed://tomwfox.wordpress.com/2010/08/07/smartmarket-test/feed/

Ping.fm has a serious problem parsing Feedburner blog feeds and Wordpress blog feeds.  Is it fair of me to think that Ping.fm may have problems with blog feeds in general?

Tom Fox
Louisville, Kentucky
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