Available in the 2016 R3 Release.

Please take a look at our help article for more information:
http://docs.telerik.com/devtools/wpf/controls/radpasswordbox/overview

Add new control to the suite: Wizard control.

Add new control to the suite: TimeSpan Picker

Would it be possible to add a new theme that accurately tracks the Google Material Design guidelines?  (http://www.google.com/design/spec/material-design/introduction.html).

Available in the 2017 R2 Release.
More information you can find here: http://docs.telerik.com/devtools/wpf/styling-and-appearance/themes-suite/common-styling-appearance-material-theme

Coming from RadControls for WinForms I did miss this control.
It didn't take me long to create my own alert controls, but it would be nicer to have them styled and behave like all other telerik controls.

A useful new control would be : RadWebcam

It would show webcam view in realtime and call a function each x seconds (or ms), would be useful for :
 - user picture to attach to its user account
 - quick product picture
 - and for my need : call an external function for barcode recognization

I think it would be easy and fast to create this control for WPF, and it would fit perfectly with Silverlight 4 (or 5 ?) webcam support.

A new theme which will follow the look and feel of Windows 10 OS and the subordinate Office 2016 Microsoft products. There should be two versions - a normal layout and touch-optimized one.

Available in the 2016 R3 Release.

A component to easily chat with visitors on a website.  It's becoming popular to be able to interact and offer support that way.  Maybe based on the Windows Live Components or something along those lines.

http://www.telerik.com/community/forums/silverlight/general-discussions/feature-request-callout-control.aspx

Add a possibility to create a ZipPackage with a password associated with it.

It would be awesome if Telerik created custom OpenFileDialog, SaveFileDialog and BrowseFolderDialog controls/windows/dialogs that would mimic the functionality found in: Microsoft.Win32.

- Differentiate from competition - Create controls that other WPF controls packages don't have
- Allow users to have common styling/views across their application
- Make it so our software doesn't have to reference Microsoft.Win32, we can continue to have a native Telerik solution
- Could make it more intuitive to program with than the Microsoft dialog (with filters, startup folder etc)

Reference post:
http://www.telerik.com/forums/why-is-there-no-openfiledialog-in-telerik

Available in R3 2017 Official Release of UI for WPF.
Check what's new in R3 2017 here: 
http://www.telerik.com/support/whats-new/wpf/release-history/ui-for-wpf-r3-2017

The new API should allow you get an SVG file and convert it in a WPF-friendly format.

If there is a control, it should also display the SVG contents.

Provide a way to convert flow formats (docx, HTML, RTF) to PDF.

Features to support:
- Text blocks with basic formatting, preferably draggable, and preferably with customizable borders/backgrounds.
- Basic drawing functionality such as pencil, brush, lines, circles, rectangles etc. Of course with color selection for lines and fill. 
- Line thickness selection. 
- Being able to move the objects around the board would be nice.
- Connecting objects with some sort of connector lines, pretty much like the map structure in SketchFlow, if you are familiar with that. 
- Some basic shapes, such as arrows and icons that can be dragged/dropped on to the board.
- Support for uploading images and dragging them onto the stage. 
- XAML export (necessary for saving a drawing)
- Printing
- Magic marker/highlight functionality
- Collaboration support. This is a big one, and I am not sure how it should be implemented. Full collaboration functionality out of the box would require a service running duplex WCF or something similar. Alternatively, perhaps Telerik could provide us customers with an API and some sample code. Then we could handle the back-end stuff ourselves.

===
Our XAML team has recently reviewed the status of this feature request. Since most of this requirements are covered by our RadDiagram Control / Framework we are changing the status to Completed.
Please follow RadDiagram documentation:
http://docs.telerik.com/devtools/wpf/controls/raddiagram/overview.html

File explorer with the drag and drop upload and just a richer interface

Add a virtual keyboard control similar to WinForms.
https://www.telerik.com/products/winforms/virtual-keyboard.aspx

Create control for fast editing/visualization of source code.

NEW Kanban Control

LIKE 
https://www.devexpress.com/Subscriptions/New-2016-2.xml#winforms
https://www.syncfusion.com/products/wpf/sfkanban

Develop Apple/MAC theme