The practice we have been recommending is just adding your external dependencies in source control. As far as I am aware, most (if not all) teams here at Telerik do just that for external dependencies as well.
We have been receiving a lot of requests for making our products useable through NuGet, but have not received too much feedback on how customers expect things to work. Besides distributing the actual assemblies, most of our products ship with a lot of tooling, which cannot be distributed through NuGet.
As far as plans go - having in mind NuGet 2.0 just got released, we are planning to reevaluate our options to ship components through NuGet. As always, all ideas and feedback are most welcome.
All the best,
the Telerik team
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