I am in the same boat after upgrading.
We get the normal message: Thank you for contacting XXX. A support ticket request has been created and a staff member will be getting back to you soon.
An email with the ticket number has been sent to xxx@xxx.com. You'll need the ticket number along with your email to view status and progress online.
At first I was using an email account running through Google apps. When I logged into that account I could see in the SENT folder all emails were actually sent but none ever came to the user (I as guessing maybe that was an MX issue and that our Exchange server was blocking it).
So, I tried to use a good old gmail address as the outgoing and now nothing is showing in it.
I do get the admin alerts but users who submit tickets get nothing.