Android 4.4 + Google Hangouts update = $20-30/month plans on T-Mobile?

I've been trying to find a conversation about this but I couldn't find one, and it's baffling me. This is, hands down, the most exciting feature to me about the Nexus 5 and Android 4.4: $20-30/month plans on T-Mobile. Let me explain:

It is all-but-confirmed that there's a new Google Hangouts app that's coming to KitKat, and the fact that the leaked images of the Nexus 5 show Hangouts in the bottom tray replacing the messenger app is very telling. Furthermore, it looks like the new version of Google Hangouts will support SMS and MMS (http://www.androidpolice.com/2013/10/07/all-but-confirmed-google-hangouts-1-3-screenshots-suggest-smsmms-integration-video-sharing-capabilities/). And The Verge just posted this article about how Hangouts was updated for iOS allowing Hangouts to support voice calling (http://www.theverge.com/2013/10/18/4853956/voice-calling-comes-to-google-hangouts-for-ios). I think it's safe to assume these features will combine with the release of Android 4.4. A very useful addendum The Verge made to that article is as follows:

A Google spokesperson let us know that, unlike using the Google Voice app, dialing and placing a call through using the Hangouts app uses data, but not any voice minutes. "If I type in a number, it sends data to Google and then Google actually calls the phone number," said Google in a statement. "This is different from what Google Voice does today (it actually dials a random number). So you're using data, not minutes from your carrier."

So, are we finally reaching the day now where we don't need texts and minutes as part of our plan? Can we finally buy the Nexus 5 off-contract for $349 and only pay $30/month at T-Mobile for 2.5 GB/month? I'm currently a Verizon subscriber with the GNex and I personally can't wait to switch and save $40/month. Heck, if I find I'm close enough to WiFi most of the time I could even do their $20/month plan for 500 MB/month. (http://www.t-mobile.com/cell-phone-plans/mobile-broadband.html)

I wanted to post this thread because I don't see anybody else talking about this incredibly tantalizing possibility. Am I dreaming or is this actually about to be a reality?