Looks like telerik is going to support Mono. This news is certainly interesting for Mono guys as it might give wings to Mono. Which is a good thing, indeed. However, the support (if it is going to happen) will probably be limited to asp.net components – they don't even mention WinForms at this point. I assume that running WinForms controls on Mono is a different story because WinForms controls are still pretty much tied to Windows API for performance reasons. I wonder if the situation will change with adoption of WPF where there is no need to hook into Windows API directly.
UPDATE: This news is not new news but old news (2 years).