March 15th, 2013 Update
Please read Import-ant News for Google Reader Users and note I will now be moving all my followers back to WordPress.com this weekend.
I will be unfollowing all blogs I currently follow in my WordPress.com Reader and making other arrangements.
From the support forum thread : The new “comments I made” feature is horrible
Thanks for the feedback folks, we’re taking this all very seriously, and rest-assured that we’re not done iterating on the new My Activity section.
I’d like to clear up one common misconception here. The idea that your comments have been injected into the Reader is simply not true.
http://wordpress.com/#!/read/following/ will always feature just the posts from the blogs you’re following
http://wordpress.com/#!/activities/ will feature posts that you have liked and commented on (plus your comments).
We’re still working to make little improvements around the new system and greatly appreciate your feedback!