Sure the IE Mobile browser is not fantastic (even the Mango version feels like it has issues), but will you be supporting the WP platform?  That would round out all the worth while mobile devices in my opinion.

Web devs have a million different frameworks out there.  Talk about how this differs (or is a companion) from using jQuery UI (looks like it competes), Knockout, extJS, etc...

It would be great if you could zoom in on the charts like highcharts,
http://www.highcharts.com/demo/line-time-series

A lot of the charting functionality there would be great.

I would like to request, for the following controls: Rich Editor, Data Filter, Masked Input for building business apps.

[Edited to remove tools already included in beta.]

To make it easier to add Kendo UI to a project, create a Ruby Gem package.

In addition to Line and Bar chart types, it would be nice to have support for the Pie chart type.

It would be nice if Kendo offered an online tool that could produce a custom, minified JavaScript download with only the JavaScript code for specifically selected features.