OK, I've been working with the new Microsoft AJAX stuff for a few months, trying to do a kind of Resource Explorer application. It's primarily hierarchical data of Resources, all of which have parent resources and child resources. Resources have literal values associated that become attributes in the xml output. I've been trying to do a lot of the things I've seen here, even using the same color scheme (I think it's from using Vista, cause it's pretty), but up to now have been using only the MS Ajax and the supplemental Ajax Control Toolkit (very much like scriptaculous on top of prototype).
Now, I'm not a big Microsoft fan, mainly becuase I have to work with their tools, but it's a requirement. So I came across this site, cried a little becuase I realized I had wasted so much time, and then went to the higher ups to show them that everything we've been struggling to implement using asp.net ajax was already done, and with better quality. I went prepared, and no concern could kill my argument, that this was better more complete, and much higher quality in both user experience and design. There was one thing that made them quiver, though, and that is the fact that all this is being done by one guy, unemployed, who will likely move on or get a job, sooner or later. Ajax is supported by the standard MS 9 or 10 year lifespan, and with 60 billion in the bank, will most likely last for the 9 years.
The concern that I cannot address, is on support. What if something breaks? What if we're trying to customize some piece and have trouble and need some help? Nothing lasts for 9 years, so let's argue with 2, maybe 3 years. It's still very feasible that Jack gets a job in a month and yui-ext goes to low maintenance mode. It also on Microsoft to make sure that upgrades are smooth, or even backward compatible. dot Net 2.0 will still work on the 3.0 redist, and if something is found to be broken, MS takes the blame and has to fix it. It's all about passing the buck, about liability.
If something goes wrong, blame MS, call MS, then wait for a fix, it's not your fault. If I implement yui-ext, and something goes wrong, or someone wants something that's not possible, and there's no support, then it has to be rewritten, and then it's my fault. It's politics, business. If I were writing my own website, I could make the decision to use this without question, but in a corporate setting with accountability, it's more risky (not so much from a technical perspective, but political). Anyway, I guess that's the catch-22 on open source. This is some really good stuff, and I'll be using on my own time for sure.
If anyone has done any asp.net ajax server side, with yui-ext for the UI layout, and integrated the 2 so that the updatePanels work, please reply or contact me. The ASP TreeView is not supported by the new AJAX framework, and I'm trying to write a yui-ext based TreeView control that is data bindable and makes callbacks that I can catch in code behind event methods. I've seen the work on the GridView, and am currently working though that code.