Yahoo! User Interface Library

Yahoo has released their own javascript/DHTML/Ajax library today. I have am using a lot of these kind of effects on the site I'm building right now. I've been mostly using Rico but have played with Dojo and Scriptaculous too. All three of those are similar in that they are built on top of Prototype, a popular javascript library.

Yahoo's Library appears to be a complete standalone library and also includes 3 User interace widgets: a Calendar, a Treeview and a Slider. Like Scriptaculous and Dojo, Yahoo's library is divided into several files so you can just load the pieces you need.

I like what I've seen in trying out the demos though I may stick with Scriptaculous going forward. Rico was a good place to start since it has the easiest setup but Scriptaculous has more momentum. I like having the prototype library available since those are a great set of functions to use in my javascript.

If I need some of the more unusual Yahoo library features (the widgets, bezier paths(!) I could see using Yahoo. Another possible advantage for Yahoo is the JSON support though all of my current use of Ajax is still using XML. Rico does have a nice datagrid component but my work is more focused on content and marketing rather than the kind of app that needs that.

Here are the links to all of the above kits, check them out!
Prototype - http://prototype.conio.net/
Rico - http://www.openrico.org
Dojo - http://dojotoolkit.org
Scriptaculous - http://script.aculo.us
Yahoo! User Interface Library - http://developer.yahoo.net/yui/index.html