I can confirm that Sprint is still charging (at least in the New England area).
A friend turned it on for his phone and sent a test message, successfully made it through, and was transcribed to his email. We did notice that there are an extra few rings before VM picks up because Sprint is forwarding on to the new number.
After a while, the charges did show up in his account on sprints website at 20 cents a pop.
Hope this helps!