As ScottGu recently posted on his blog, Microsoft have recently released a set of charting components. Several people followed up with comments on his post asking whether it was possible to use them with ASP.NET MVC. The good news is that it certainly is, if you are using ASP.NET as the View engine (the default). And there's actually relatively little that you have to do. This post outlines the steps you'll need to take to get it up and running.
You'll need to first add the references to the appropriate assemblies (System.Web.DataVisualization and System.Web.DataVisualization.Design if you want design support). You also need to add a couple of lines to your Web.Config file. In the <controls> section, you will need to add:
1: <add tagPrefix="asp" namespace="System.Web.UI.DataVisualization.Charting" assembly="System.Web.DataVisualization, Version=184.108.40.206, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/>
You'll also need to add a new line to the httpHandlers section:
1: <add path="ChartImg.axd" verb="GET,HEAD" type="System.Web.UI.DataVisualization.Charting.ChartHttpHandler, System.Web.DataVisualization, Version=220.127.116.11, Culture=neutral, PublicKeyToken=31bf3856ad364e35" validate="false"/>
It's then pretty much simplicity itself to add a chart to a view page - you just drop it on as a server control exactly as in the examples in the sample project linked for Scott's post. You'll obviously need to call the code to insert the DataPoint objects into an appropriate Series, and this will probably lead to a few lines of code in the code behind file, but given that the data-transfer objects between the controller and the view are generally reasonably well structured, this code should be both readable, and fairly short, so I don't think that it's really a problem.
I think the best approach if you are interested in doing this is to simply have a go and see how it gets on. I think it's a nice simple solution myself and certainly doesn't represent a great deal of overhead to get the result out.