Google has released Google Reader, its web-based RSS Reader that comes directly ic competition with Microsoft's Start.com.
For the quick test I've done it seems to work quite good (despite the bad comments I've listened around). The interface is quite similar to Gmail (with the useful "starred" feature where you can mark important posts and retreve them easily) and the feed navigator that you have on the left side is really cool (it scroll between posts).
Obviously the site makes an extensive use of DHTML and Ajax/XMLHTTP, that allows the system to update the page content without a full server round-trip.
What I'm asking now is why the decision to release this tool as a standalone application and why not integrate it with Gmail. Having the possibility to work with this tool directly into Gmail I think it will be very cool and most useful.