Same here, I volunteered Friday and Saturday, and the voucher email was in my mailbox this morning. I plan to use it for a FPX when I travel with a marching band in the middle of April, so I had plenty of time, but it was good to get it, print it, and file it with my other trip info!
It kind of surprises me that Disney does not appear to be considering extending the program. It costs them very little in the long run, it's great PR, and more importantly, the agencies involved are getting volunteers they never had before. And those volunteers are enjoying their time, and I am sure many of them will plan to volunteer again. Glad I could be part of it!