The read/unread feature of the RSS is very well done and a welcome addition. However, there is still what I believe is a bug.
BUG - Feeds like http://www.warp2search.net/news/rss will truncate older items and correspondingly the RSS feed in SmarterMail will truncate items but it does mark the new items as unread. I think it would be better to keep a minimum number of days of the feed from previously read items.
FEATURE - A Mark Read on the All Feeds would be a welcome addition.
FEATURE - I still think right clicking on the feed name and opening the raw feed in the web browser would be a welcome addition.
Thanks again for the work done so far.