Now you can read all comments of your Picasa web album in your favorite RSS reader. There is no need to go back to the website to check new comments.
Just subscribe to feed://picasaweb.google.com/data/feed/base/user/USERNAME?kind=comment&alt=rss&access=pub
(replace USERNAME by your Picasa username) You will receive all comments of all photos in all albums through the feed.
It seems that Google does not provide this link explicitly. There is an RSS link of all albums. I looked at the link and wondered what will happen if the link parameter "kind=album" is replaced by "kind=comment". Then I found this useful comment feed link.