On Windows 7, Vista, and Server 2008, Adobe Reader 10.1 installs ARMsvc.exe as part of the Updater. It is a Windows Service that runs in a System context. The new service enables silent and automatic updates on machines where a user has configured the application for automatic updates. (For automatic updates, choose Edit > Updater > Download And Install Updates Automatically or Preferences > Updater > Download And Install Updates Automatically.) Without this Service, the user confirms elevation through the User Account Control (UAC) dialog box during the update process.
The service has no scheduler and does nothing on its own. The Updater uses the service when it needs elevation. By default, the Updater itself checks for updates every three days after the last successful check.
It is not configurable except that someone with the requisite privileges can stop or disable it. Settings for changing the update interval or check mode belong to the Updater. For details, see http://kb2.adobe.com/cps/837/cpsid_83709/attachments/Acrobat_Reader_Updater.pdf.
Yes. Like any standard Windows Service, it can be configured using Windows Service Manager. If configured to be stopped or disabled, the Updater cannot use it.
On Vista and Win 7, if User Account Control (UAC) is turned off, the Updater is disabled for Standard users. If UAC is on, Updater is enabled for Standard users. However, silent installs are not possible for standard users because it's necessary to provide Admin credentials to elevate the installation of updates. In this workflow, standard users are switched to user interface mode (with displayed dialogs) to provide credentials. (User modes switch even if the Updater preferences are set to run in full automatic mode.) Standard users can't install the updates without entering the credentials even with the introduction of armsvc.exe.