I’ve always referred to their entire network as TWiT. If memory serves me correctly, all their shows (not just This Week in Tech) used to begin with a bumper that said “Netcasts you love, from people you trust. This.....is TWiT.”

They still do. Here it is at the start of this week's MacBreak Weekly episode (at 24 second mark):

https://www.youtube.com/watch?v=PFSJ2axjbW4&t=24s

They actually do, yes. Source: Listened to many Leo Laporte podcasts over the years, but stopped a couple of years ago, due to the noise/ads to content ratio.

I used to listen to TWiT but signed up for Audible based on their recommendation of the service and I stopped listening to podcasts and listen to audiobooks!

It's like saying: I stopped reading newspaper, and read novels only now!

Even though they share the same channel (text, audio, etc.), those are not replaceable things. Or at least that's my opinion.

TWiT is the network as a whole. This Week in Tech is just one show (the original show?) on the TWiT network along with Windows Weekly, Security Now, etc.

I've always called it TWIT.

Which is also the name of the network, which has a bunch of other shows besides TWIT.

Yes, we do actually call it TWIT