OK all, Since there were no responses to this thread, I stopped by the dealer today and asked their resident "Entune Guru" about this particular model's updates. Here's what he told me (paraphrased, of course):
1. The software version I have is the most recent....even though the vehicle is basically a year old and has NEVER been updated. So all those patches that the nav versions have gotten over the past year do not apply to the Audio Plus version.
2. The Entune Audio Plus unit is NOT supported by the Entune app team (basically, it's a red-headed step child in the Entune family).
4. They changed this on the 2014 model, and took away your ability to register this as an Entune device (for those of you who, like me, were wondering why you were getting the "invalid VIN" error when you tried to register with Entune).
5. The Toyota website still says my vehicle is "Entune" app enabled. It lies
Bottom line is that for anyone with a 2014 or later, and an Entune "Audio Plus" unit.......You have a glorified radio that really isn't going to get much fancier than it already is...or much (if any) updates.
For me, it works and isn't worth replacing. That said, had I known what I do now, I'd have beat down the price a couple hundred more during negotiations. No way is this worth $680.00 in my opinion. I'd have rather added a couple hundred more and gone with a high end Kenwood/Garmin unit.