After looking at the available options, I'm looking at making a plugin for jQuery (and coincidentally, a library for ASP.NET MVC) that will provide some simple methods for dynamically adding objects to a collection of a ViewModel.
I speak of things like this ( http://www.highoncoding.com/Articles/640_Adding_Multiple_Nested_Data_in_ASP_NET_MVC_Application.aspx )
I was wondering if there is already anything out there like that, though, before I start building one of my own.