I was just searching for a syntax highlighting Python-script control in WPF and found this site - looks like a great control! I would also be interested in a silverlight edition - if possible with a compatible API to the WPF edition.
It is becoming more common to develop dual-deployed applications targeting both WPF and silverlight (perhaps with a subset of features on SL). The technique to do this is use some pattern like MVVM and separate out the View to be as thin as possible, then duplicate only the view code (Xaml & code-behind). The Vm's and other business logic code is added to the WPF project as a link so it can be compiled twice.
I'm sure you know that already! Just saying that if Actipro does decide to persue silverlight components then please try to get the API in both WPF/SL as common as possible as this will ease this process.
Another control set that does this (the only one actually) is telerik's rad controls. I am considering buying this set as I am interested in Ribbon, Docking, Treeview and GridView controls in both silverlight and WPF. However its mighty expensive. So if Actipro did say manage to release "Silverlight Bundle" with a compatible API to the WPF you could count me in as a customer for both! :D