Isn't this all still speculation? We've heard some Q1 or Q2 or "by summer" rumors, but no official dates yet. We haven't even seen the phones, other than spy shots. Just like we have no 'legitimate' confirmation of an iPhone on Big Red.
Personally, I'm waiting for the last of the original Incredibles to go Bargain Basement. Though the new phones will be fast and possibly have better screen resolutions than the current generation, I would not be looking forward to paying for LTE capability, even when it's not offered in my area (just like Sprint). I think $75/month (that's with a discount) is enough. You watch, they'll jack the $30/month for data up to at least $40 for LTE phones, coverage or not.