Fully agree with idea, it's quiet needed feature, at least while program is in beta.
But realization imo should be something like:
Add item in Main_menu => Help => "Check for updates" with popup window. In window something like 3 buttons ("Check", "Update"{if available} and "Download latest test version"), progress bar and somekind of label to show update results.
P.S. it would save many kitties ^_^