I found this by accident the other day. While I thought I was in Safari I pressed Command 4 to load the bookmark I have there, but instead iTunes was active and it flicked from my music to my Podcasts.
As it turns out, all the sections all have a shortcut assigned.
So when you hold command followed the the numbers below, it will show you that Section
- TV Shows
- iTunes U I don't have anything in here so it doesn't do anything
Hope this helps, it's always good to have a couple of good shortcuts. It will work in Safari as well with the bookmarks you have in your bookmark bar.
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