I was trying to configure and use the Visio Graphic Service in my SharePoint 2010 Beta environment and for some reason, this service along with a few others were totally missing from Application Management –> Manage Service Applications. Where were all the other service applications???:
I think it’s a beta bug as I have been able to reproduce this on a fresh install on a production physical farm environment as well as my own local image.
Don’t ask me why or how but I was able to finally able to see the services by deactivating and reactivating the Visio Web Access farm level feature by going to Central Administration –> System Settings –> Manage farm features under Farm Management
***Update***: The same problem was occurring on our production problem but this time I didn’t even have the option of enabling the farm features. It turns out that we need to install Office Web Apps  on the SharePoint 2010 Server before those services will show up.
“Installing Office Web Apps on SharePoint Server 2010 adds the Word Viewing Service Application, Excel Calculation Service, and PowerPoint Service Application to the list of available SharePoint shared services. Additional SharePoint services are not required to edit in Word or for OneNote files. Installation also provides a series of web pages and handlers, each used by the Word, Excel, PowerPoint and OneNote Web apps. “
Refer to Microsoft TechNet  for more information.
***Update***: The Visio Graphics Service is still missing and there is no option to manually create the service on the service applications page:
I have a discussion thread on the SharePoint 2010 beta support forums  that is tracking this. They seem to indicate that it might be an install problem. Hope it gets resolved soon, I don’t want to recreate my QA environment.