I used the original AT&T Galaxy Tab as a phone for 2 1/2 years. The hardware worked fine. Never heard of a "voice radio." I have heard that AT&T had Samsung remove an earpiece speaker. If true, then you'd have to use your Note 8.0 with a wired ear phone, Bluetooth device or as a speaker phone. The critical issue for me is: how will this item sell? I don't see AT&T selling a lot of them. To mean that means that the endusers will see fewer ROMs down the road. Developers here can probably root this device and unlock the bootloader. Someone will -- at some point in the next few months -- make a ROM with voice capabilities available. And don't expect "official" Cyanogen releases.
However, AT&T may block the the Note 8.0 from access to voicecalls based on the IMEI. Now, the IMEI can be hacked, but that's -- legally speaking -- a gray area. Altering IMEIs to get "free" service is illegal. Doing so to access service that you're paying for violates the letter of the law, but not its intent and won't bring about any dire result.
At the end of the day, you may be able to access (after jumping through a lot of hoops) AT&T voice services and use the phone for a year or so, but it's not worth the bother. Get the S4 and tether a decent cheaper wifi tablet to it. Yes, it's nicer to have one device, but under this conditions impractical.