Widget not showing top rank articles or not showing correct rank (compared to feed)

If you look at my feed (http://www.postrank.com/feed/d24ad720...) you will see that for example an article from December 5, 2008 has a rank of 9.8 and it is not showing on the widget that is in my site (www.uglydoggy.com).

On the other hand an older article (from October 2007) with a *supposedly* lower rank is in fact showing in the same widget. Now, the reason I say supposedly is because the rank that appears in the widget is not the rank that appears on the feed (in the widget has a rank of 8.8 but in the feed it has a rank of 10) -what can explain why this older article appears in the widget- but does not explain why then the rank is not the same in the widget than in the feed. I am a bit confused by all this and was wondering if it is something that is not working or if there is something I should be doing that I am not doing.

Thanks in advance, Sandra :)