I don't see the point of such notification and it will also be an easy target for abuse. Somebody can bump the version every day (or week, as often as that registers) and submit the app as "new" thus staying featured perennially in the "Recently updated" list.
Public channels and their updates have to be approved by Roku, so I don't think there's a danger of someone abusing the update process.
I think there's great utility in a row in the channel store that indicates what channels have been recently updated. We're not talking about flashing lights and sirens, just another row next to the "New" row. There may be a channel I tried out awhile back, but decided for whatever reason wasn't quite useful enough to clutter my channel list. Or maybe a game that I completed and uninstalled. If I have no way of knowing it's been updated, then I may be missing out on some exciting new features and/or new levels. In-channel notification is only useful for channels I already have installed and regularly use, which I'll automatically get the updates for anyway.
My Channels: http://roku.permanence.com - Twitter: @TheEndlessDev
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