I hate to resurrect this thread, but...
I've always been bothered by the way MC handles automatic updates. I don't want to turn off automatic updates, but I WOULD like at least have a chance to CONFIRM the installation before it actually happens. Something like a prompt that says "An update for JRiver Media Center has been downloaded. Would you like to install it now? [Yes][No]" (or something similar). And if I happen to select "[No]", a message saying that I can install the update later via the menu "Help/Update Channels/Check for updates...". Simple.
More importantly, the update installation window doesn't make it CLEAR that this IS an update. It looks and works almost exactly like the window for an initial installation of MC, with only a brief text message flashing by as the progress bar moves along to indicate what is happening. I feel the window ought to have a static message at the top that says "Updating Media Center from version XXX to version YYY". This might especially help newer users understand what is going on.