Over on Google-Plus, Tantek Celik asks if Bloglines was the first web-based RSS feed reader.
The first was my.netscape.com, which according to Scripting News, was first available on February 11, 1999.
We launched our competitor, my.userland.com, on March 27, 1999.
Archive.org has a snapshot UserLand's site from 1999, but seems to have lost their archive of my.netscape.com.
Our reader took the approach eventually adopted by Twitter and Facebook.