Ian,
Great Question, when you talk about Windows Services what do you mean.
Couple of things to note,
SoftGrid can do application services that run when an application is launched, but any service that runs in the background all of the time would not work. That is because SoftGrid applications run when they are launched and the softgrid software to support Virtual Environments starts after a user has logged on and not when windows starts.
Another problem is based on how sequencing and the virtual environment work you can't capture the identity information that is critical to most Services (ie Exchange, SQL, etc.) So at this time those aren't supported and wouldn't work.
Hope this helps, but if my understanding of your Windows Services is wrong please correct me and I will work on my answer
Matt McDermott